Information Studies


Tributes to Iain Stevenson

The department has been very saddened to hear of the sudden death on Wednesday 1st March 2017 of Iain Stevenson, Professor Emeritus in Publishing. Iain was a member of DIS for nearly ten years and made an enormous contribution to UCL, leading the successful development of both the Centre for Publishing and the MA in Publishing. The picture above shows him with the 2012/13 cohort of MA Publishing students. Although Iain formally retired in 2015, he continued to work with, support and inspire colleagues and students in his Emeritus role, and is sorely missed. This page shows some of the tributes that have been paid to Iain. If you would like to add a tribute, please email your text to s.rayner@ucl.ac.uk.

Iain Stevenson with his MA Publishing students
  • "I first met Iain at an event to discuss publishing education and it was he who first suggested I could use my professional experience to teach budding publishers and in so doing he opened up a whole new career to me. Iain gave me my first teaching opportunity in publishing education at City University and later at UCL. He was a kind and encouraging colleague who could always put a problem in perspective based on his long professional and academic experience. His knowledge of the publishing industry, and its characters, was extensive and he was generous in his advice to colleagues and students alike, who like me will all miss him." - Nick Canty, Lecturer, UCL
  • "Professor Stevenson interviewed me for UCL's MA in Publishing with Mel Ramdarshan Bold - he's partly the reason why I'm here today. He will be missed." - Claire Ormsby-Potter, student, MA Publishing 2016-17.
  • "A wonderful supervisor and fountain of knowledge, he will be deeply missed." - Dr Aislinn O'Connell
  • "When I was in my early 30s and made redundant from my job in publishing, I was in Waterstones and saw Book Makers- Iain's book. I read it from cover to cover. When I started at The Bookseller magazine, I met Sam Rayner. I was in her office talking about careers events for students and I saw a poster on the wall advertising that same book. Sam explained who Iain was. We got talking about studying publishing and I decided to apply for a PhD. Before I read his book I would never have realised that publishing had such an interesting history and that I could study it. I was hoping to meet Iain again when I was further into my PhD to show him what I had learnt. Now I will make sure I stay on track to finish it and I will dedicate my work to him instead. I didn't know Iain well but I am so glad I found his book because it gave me a new purpose. I wish his family well at this sad time." - Maria Vassilopoulos, Phd Student, UCL
  • "Quite apart from his considerable skills and status as an academic and professional publisher, Iain was a wonderfully kind and warm individual who really cared for both his students and his colleagues. We will all miss him." - Rob Miller, Head of Dept.
  • "Iain was the most incredibly generous and warm person who enrichedthe lives of so many. My thoughts are with his family and friends. The hundreds of Publishing alumni whose careers he helped to forge and everyone who knew him will miss Iain terribly #rip" - Nick Coveney, Digital Marketing Director
  • "Iain was was the external examiner for my PhD and I appreciated his encouragement to me, a young researcher"  - Dr Rachel Noorda
  • "Devastated to hear of the death of @PROFSTEVENSON - far too soon.  A wonderfully warm and funny man, so much energy, so many anecdotes. #RIP" - Alison Jones, @bookstothesky
  • "Until 2015, the year in which he retired, Iain Stevenson had been professor of publishing at University College London, and was responsible for establishing UCL as one the leading institutions in the UK teaching contemporary publishing practice at masters level. He was the author of many articles and books, and published Book Makers: British Publishing in the Twentieth Century in 2010. He was also a frequent contributor to discussions on SHARP-L.  Before entering academic life, he had had extensive experience of the publishing industry having worked for, among others, Longman, Macmillan, Wiley, and the Stationery Office. He was trained as geographer and had a lasting interest in maps and their publication. He had also made a close study of postal systems, and these interests combined allowed him to bring a new perspective to UK and international book history. A brief comment from Iain on the significance of the book post in the 1850s in Britain, or of the Universal Postal Union, could help snap things into focus and solve problems of book distribution and sales that had seemed intractable. His wide knowledge and intellectual flexibility meant that he was able to make a significant contribution to the development of the history of communication in the UK.  He was a delightful and kind man, and will be much missed by his many friends and colleagues." - Professor Simon Eliot, IES
  • "I first met Iain at the Society for the History of Authorship, Reading and Publishing conference in Toronto in 2009. The idea that he might be the External Examiner for my viva was broached and Iain responded by saying he could be bribed with scones. Iain did end up being my external examiner and his generosity, fairness, sense of humour, and expansive knowledge of the subject area made my viva such a fun and wonderful experience. Iain was such a generous academic, especially to early career researchers, and played an integral role in the development of my career. I feel privileged to be working at UCL Publishing - the best team/colleagues I could hope for - and I'm grateful to Iain for creating the programme. Iain was my colleague, mentor, and, most importantly, my friend. I feel blessed to have known him and will miss him enormously."  Dr Melanie Ramdarshan Bold, UCL
  • "Iain was an enormous resource in Publishing Studies. He was so welcoming and generous when I visited UCL a few years back, and he had spent some sabbatical time here at Simon Fraser a decade or so ago. We will indeed miss him; my condolences to all who knew and worked with him."- John Maxwell, Simon Fraser University
  • "Professor Iain Stevenson was a huge support in the early days of bookcareers.com. He'd just launched the highly commended MA in Publishing and was present at bookcareers first Careers Clinic, where he encouraged me to 'think big'.  Over the years his advice, backing and latterly friendship, has been an immense help to me and the work I do. Always a friendly ear, a word of encouragement or insight into the current machinations of publishing made him a great mentor and associate.  He has left us far too soon.  My thoughts are with his family, colleagues and all who knew him."- Suzanne Collier, bookcareers.com
  • "As a student, I found an affinity in Professor Stevenson’s interest and passion for history and the business of contemporary publishing. His guidance and encouragement reinforced my own interests and career aspirations. I’ll remember Iain for his extensive knowledge but also for his approachable nature and encouraging influence.” – Jon Newbury, Teaching Fellow, MA Publishing, UCL
  • “Remembering Iain during my time at UCL in 2009/2010. He has been a great teacher and I will forever remember his passion and knowledge of the publishing world, he will be missed enormously! My most sincere condolences to his family.” – Elisabetta Audisio, alumni, MA Publishing 2009-2010
  • “Prof. Stevenson was such a major figure in my youth, education and future career choices that this news has come as a terrible shock. I feel lucky to have been given the opportunity to know him during a very important time of my life. My deepest sympathies to his family.” – Diana Copeland, alumni, MA Publishing 2009-2010
  • "I knew Iain for more than twenty years. We were both members of the Lanarkshire Philatelic Society, the Scottish Postal History Society and Fellows of the Royal Philatelic Society London. He was very knowledgeable on several aspects of postal history and was very generous in sharing his knowledge. We were planning a book on the Thurn & Taxis Post which carried mail throughout the Holy Roman Empire; and a few weeks ago we were planning his visit to Perth to give the Tom Rielly Display at the Scottish Philatelic Congress and then a few European trips to work on the book. Iain was great company and didn’t mind being teased about coming from the Wishaw area!" - Alan Wishart, FRPSL
  • "Iain was one of the most engaging and memorable presences at book history conferences over many years, a fount of knowledge and anecdote about British publishing, a generous and distinguished scholar, and a warm and humorous man. My sincere condolences to his family and friends." - Professor Patrick Buckridge, Griffith University
  • "I worked as Iain's assistant in my first ever publishing job, from 1988 till about 1993, when he went to Wiley's. He taught me an enormous amount, and I went on to become a commissioning editor. We met up sporadically after that, then lost touch a bit after I had my daughter and subsequently left publishing behind in 2005. Please do pass my sincere condolences to his family." - Nicola Viinikka, Education/Publishing Professional
  • "I met Iain at the SHARP conference in Montreal - it was so evident to me that he was a lovely man who was held in so much affection by those in publishing history and particularly by his colleagues at UCL. My thoughts are with the UCL Publishing team , his family and friends and the department." - Dr Nicola Darwood, Senior Lecturer in English Literature, University of Bedfordshire
  • "Iain accepted my second book for Belhaven and then took it with him to Wiley. It was a pleasure to work with him and he went out of his way to encourage a new author. He was a very warm and friendly human being and it is a shock to hear of his untimely death, particularly as we are about the same age." - Dr Steve Williams
  • "I am shocked and saddened to hear this news. Only a month ago, Iain answered a query that I posted to this list and helped me with my current research. With condolences to his family, colleagues, students, and friends" - Professor Marguerite Helmers, University of Wisconsin, Oshkosh
  • "I just wanted to add my shock at the news about Iain. Many of us saw him only on Tuesday over lunch at The Stationers' Company where he joined us for the annual Service at St Pauls.  As Controller of Her Majesty's Stationery Office, I worked with Iain in his time at TSO and later at City University where he set up the publishing MA and then at UCL. His love of stamps and printing was rooted his publishing career." - Carol Tullo
  • "I first thought Iain was a bit gruff, as he proudly declared the overarching importance of publishing  and the role UCL was to play in educating  students for the industry. I soon found his comments and insights rich with publishing lore, and his sidelights on postal communication both amusing - I enjoyed the TV series Taboo with greater delight as I followed his philatelic observations online - and highly pertinent to the wider history of publishing. He was convivial and warm man who I got to know through out publishing networks. My deepest sympathies." - Professor Alexis Weedon, University of Bedfordshire
  • "It is sad news indeed to learn of Prof. Stevenson's passing. I first met Iain as director of the United Nations University Press when he was with Pinter Publishers, one of our co-publishers. I met again years later after we both joined SHARP. He was a lovely fellow and still had so much to offer to the world of publishing."- Amadio Arboleda, Adjunct Professor, Josai International University, Tokyo, Japan
  • "Iain had been my Phd supervisor since 2013.  He was always a generous and supportive guide with a deep knowledge of the book trade and its history. Having been a publisher himself, he had an insider's understanding of how the cogs of the trade all fitted into place.  He clearly took great joy from teaching and talked with immense pride about the many successes of his students. He had a knack of talking about the things that fascinated him in a way that made them fascinating to everyone, a true teacher.  It seems particularly cruel that his retirement was to last only a short time, I know he was looking forward to his involvement in several scholarly projects and to writing articles that will not now be written. I, and the rest of his students, will be always grateful for the kindness and care he lavished on us." - Rachel Calder, Phd Student and Literary Agent
  • "I am very sorry to hear the news that we have lost Iain Stevenson.  I only met him the once, at a one-day course of some sort in Leicester, England, but this prompted me to read his 'Book makers', and he certainly earned his place (in the list of references) for my bibliography of Curwen Press book output during Oliver Simon's time at Plaistow.  http://www.sinenomine.co.uk/curwen/  I found him a most approachable and helpful person, and supportive. We shall indeed miss him."- Robin Phillips.
  • "I too am shocked and deeply saddened to hear we in the book history / publishing studies community have lost Iain. I have fond memories of Iain at an hilarious session on Scots-language publishing at a book conference in Boston in 2006 complete with readings, and of Iain bellowing with laughter at some of the more ribald dialogue and adding his own Scots heckles.  He is also the only person I ever heard work a mention of Clarice Cliff into a paper on map publishing, also at the same conference. I've been seeing Iain at SHARP events for at least 15 years.  It's hard to imagine him not joining us in Victoria in June."- Associate Professor Simone Murray, Monash University
  • "I only met Iain a few times but on each occasion I came away richer in knowledge, challenged by his expertise and uplifted by his passion." - Judith Watts, Publishing Lecturer, Kingston University
  • "I was stunned and saddened to hear of Iain’s death. I knew him for over twenty years as a member of the International Banknote Society. He loved all things paper. Convivial, curious, kind and always generous with his knowledge, we will miss him terribly. My sincere condolences to his family." - Claire Lobel
  • "Iain Stevenson and I became colleagues when we both began working at The Stationery Office in 1997. This soon grew into a long-standing friendship as we endured time away from our homes together in Norwich and shared conspiratorial conversations over many lunches and dinners. One of the good guys of publishing, Iain loved his world and sphere of influence, in sharp contrast to some of the other passers-by. It was a privilege to watch and talk to him about his transition to academic life and to share a small part of that with him. He helped me and Dunedin Academic Press and especially brought to our friendship his wit, humour and wisdom. A fine friend, cruelly taken too soon. My sympathies are with his most loving family." - Robert McKay, Director, Dunedin Academic Press
  • "In addition to the academic contribution he made to the Department, I will remember Iain as a wonderfully kind and generous colleague, as well as a warm and funny man.  He was many people’s choice of an internal referee for promotion bids, and had a considerable success rate.  When he was my referee I was touched by the evident time and effort he made to acquaint himself with my academic interests, which must have been a complete mystery to him. We also shared a love of the niche and the bizarre in book titles, fertile common ground for publishers and librarians.  He was always trying to persuade me to use ‘Seahorses’ as a example in my practical classification class, in the certain knowledge that it would mislead the students - it would have of course, being nothing to do with marine fauna, but a study of a set of postage stamps, another of Iain’s personal passions.   On one famous occasion, when visiting one of his publisher cronies, he spied a book on the table, and crying ‘I know someone who’d appreciate that’, bore it away with him, later to present me with the wonderfully titled ‘Cheese problems solved’, which greatly amused me, and cohorts of students since. That very real involvement with the publishing profession over a long career before academia will  be a tremendous loss to the MA Publishing programme, and to the Department more generally.  Not only did Iain have a fantastic working knowledge of the publishing industry, but during his career met with many well-known people, authors and publishers, and persons in public life.  He was equipped with an apparently inexhaustible supply of anecdotes, all of them entertaining, which he shared readily and wittily, making our working days a little richer and a little less dull."-  Professor Vanda Broughton
  • "Iain was an enormous support to students and junior scholars in particular. He was a powerful advocate, and so supportive of new ideas and approaches. I, for one, will miss his constant interest and enthusiasm in my work, and I'm quite sure I am far from alone in feeling that way. Thoughts are very much with his family and loved ones." - Dr Leah Tether, Bristol University
  • "I met Ian for the first time about 12 years ago, when he picked up a very half-baked research proposal, and encouraged me to take it to the next stage. The same relaxed, cheery support came my way at every step, through tough times, until the PhD was finally done. He made that kind of support look easy, but it was only later that I understood how much he was doing behind the scenes to smooth the way. Like many others, I got the benefit of that unusual mix of shrewd judgement and heartfelt enthusiasm – and a sheer sense of fun – which extended beyond the bounds of duty. How many times I faced a problem and thought – I must find out what Ian thinks. He was the centre of a world that now feels the loss, but also remembers what we have in common." - Dr Susan Greenberg, Roehampton University
  • "Iain was one of the people whom one really liked to see, and with whom one enjoyed conversing, at conferences, after meetings and so forth. He was always very supportive. The extreme sense of being shattered that so many of us feel at his death speaks for the esteem and affection in which we held him. Sincere condolences to his family." – Dr Karen Attar, Senate House Library, University of London
  • "We all remember Iain as a distinguished publisher and professor of publishing, but some may not know that his early training was in geography. He never lost his love of the subject, remaining in close contact with colleagues at UCL, attending happy and sad occasions, and being an active Fellow of the Royal Geographical Society. His first degree was from Glasgow University and then he studied for a second MA at Simon Fraser University. He decided to enrol for a PhD at UCL, where he joined the group of historical geographers in the autumn of 1974. I was immediately impressed by Iain’s breadth of knowledge and his interest in France – my own area of expertise. He decided to work on the impact of phylloxera (a vine disease) on viticulture in southern France for his thesis, and I had the pleasure of being his advisor. Not that much advice was needed since he defined his theme, attacked the archives in Paris and Montpellier with vigour, and wrote up efficiently. A couple of academic papers came out of that early work. There were few academic jobs going at the time so Iain decided upon a career in publishing – and never looked back. We remained in touch, having lunch together a couple of times each year and more frequent cups of coffee. We even co-authored a paper about UCL geographers and the Collège des Ecossais. In some ways, Iain was an ‘old style’ publisher, always interested in his authors as people, visiting them and situating them in their academic context. He was a fount of knowledge about British and French geographers and often advised me on aspects of the recent history of geography on both sides of the Channel. It was a real pleasure for me to act as a referee for his chair at City University, and then to welcome him as a colleague at UCL in 2006. I thought of Iain during a recent trip to Montpellier when I visited the old archives where he worked so hard in the 1970s. Our last time together was in Paris, where he was attending a philately conference. We enjoyed dinner together and shared a good bottle of wine. He was full of information about geographers, his research into map publishing, and other projects in the offing. I and the other ‘old boys’ in the Geography Department at UCL will miss him greatly. He was a good friend indeed." - Hugh Clout, Professor Emeritus in Geography, former Dean of Social and Historical Sciences, UCL
  • "Iain's death came as a huge shock personally and professionally. He was such a great ambassador for industry, such a great mentor for many, such an enthusiast, and above all he was a mensch. The world is a poorer place." - Richard Charkin, Director at Bloomsbury plc
  • "Like others, I was shocked and saddened to learn of Iain’s sudden and tragic death.  He was a unique talent, outspoken in his views, self confident in his assessments, a font of knowledge, a sly wit and someone who had the ability to surprise you with the arcane knowledge he possessed within that capacious brain of his. I worked with him on several projects, and co-commissioned him to contribute to the Edinburgh History of the Book in Scotland, for which he delivered finely written pieces that were erudite, knowledgeable and personable in tone. I most recently enjoyed  his Facebook postings expressing mock dismay at the Philatelic infelicities of various BBC programmes then airing –the word ‘ridiculous’ frequently punctuating his disgust that the BBC had clearly not called on his expertise to fact check whether postal letters were franked and delivered to houses in 1819, or tut-tutting that a particular programme had featured the wrong official seals on documentation lying around the scenery of government offices. Hilarious in the way they perfectly displayed his academic credentials and keen eye for authenticity in historical contexts. I will miss those interventions more than words can say." - David Finkelstein, Chair in Continuing Education, Head of the Centre for Open Learning, The University of Edinburgh
  • "Iain’s passing is a tremendous loss for all of us who work or have an interest in publishing studies and the history of the book. I shared many enjoyable moments and conversations with him, discussing all kinds of topics including ideas for books and articles we both thought the other should write. I lost count of the number of times he would unexpectedly and cheerily pop up at an event without my having realised that he had yet another interest or area of knowledge which he was willing to share and debate. He will be greatly missed."  Dr Andrew Nash, Institute of English Studies
  • "Whenever we met Iain and I found ourselves talking about wine. From his PhD he had a strong academic interest but he also had a very discerning palate. For a few years he was the wine correspondent of the Geographical Magazine and it was great fun to be regaled with stories of the cases and bottles of wine he received from growers and merchants anxious to promote their wares (he didn’t). For the Magazine he wrote one critical piece on the (largely poor) use of maps in wine books and which  resulted in at least one author dropping him from her tasting invitations. But maps improved subsequently."- Emeritus Professor John Salt, Migration Research Unit, Department of Geography, University College London
  • "I only knew Iain for a short while, having worked with him on a PhD examination. However, during that time he made a big impact on my life. He was an intellectual of the highest calibre as well as a warm and inspiring human being. He had a fantastic and infectious sense of humour and was able to find laughter even in the darkest of moments. His sense of adventure was liberating. It was a genuine joy and privilege to have known and worked with him and his loss feels immense. My very heartfelt condolences go to all his family and friends.” - Dr. Louise Cooke, Reader in Information & Knowledge Management, Head of Information Management Discipline Group, Loughborough University
  • "Although I knew Ian for only a short while as a colleague at UCL I was fortunate to be able to take his course in modern British book trade at the London Rare Book School and to have lunch with him at conferences after. His generosity, humour, and love for publishing and books were obvious for all to see. I offer my deepest sympathies to his family." - Frederick Nesta, University College London - Qatar
  • "As Immediate Past Master of the Stationers' Company I would  like to add a tribute to Iain and to acknowledge the great contribution to he made to the world of publishing and its future. He was a highly respected member of the Stationers' Company. His sudden death was a great shock to us all and he will be sadly missed. I shall think of him on his last visit to the Hall on Shrove Tuesday when he greeted me with characteristic warmth. Our thoughts are very much with his family who must be hugely proud of a man who achieved so much and was held in such high regard by all ages." - Helen Esmonde
  • "My sincere condolences to family, friends and colleagues of Iain. I will always hold dear memories of the kind curiosity Iain showed me and fellow presenters at SHARP and other book history conferences and meetings. May his work live on in all of us."- DeNel Rehberg Sedo, PhD, Professor, Department of Communication Studies, Mount Saint Vincent University
  • "This is very sad news. I didn’t know Iain well but he was one of those people who very successfully brought together his career in industry with his academic life, with great enthusiasm. He was, even in my small dealings with him,  always very supportive and genuinely interested in my work. My thoughts go to his family and friends." - Frania Hall, Course Leader MA Publishing, London College of Communication, UAL
  • "I met Professor Iain Stevenson in the autumn of 2002 when I arrived in London to begin my year studying for a master's in publishing studies at City University as a Chevening scholar from Egypt. Iain's welcome was the best any student could hope for: he was warm, friendly, kind, and so interested in and enthusiastic about his field that he fired up everyone around him too. I still remember that first trip to the British Library, and the pub crawl that followed. That year set me on a path to a new career, and I finally figured out what I loved to do, working with books. I will miss his Facebook posts about stamps, wine, maps... he was always curious about and interested in the world and the people around him, an endearing trait. He was such an encouraging professor and teacher, truly one of the best I've ever had. The world is poorer without him in it, but is so much richer for his having been in it. He touched so many lives. Rest in peace, professor." - Jehanne Moharram
  • "I first met Iain when we were 12 years old, 55 years ago. We were in our first year at Wishaw High School. We have been friends ever since.


    Ours was a mutually cherished friendship. We had different interests, for example, he with stamp collecting and me with sport. We also had shared interests. We were both in the cast of Gilbert & Sullivan operas staged by our school – The Gondoliers and The Mikado to name but two. Neither of us could sing and I remember one lunchtime rehearsal with our music teacher whom we called old Sid. Iain was late and on entering the room and being admonished by our teacher for his lateness, Iain said “Sir, you can’t hurry curry” – a typical off- the- cuff remark.

    We were in the chorus of The Mikado and in one scene we had to come on to the stage in the chorus line with Iain directly in front of me. As anyone who knew Iain can imagine, it was difficult trying to keep in step with him while singing at the same time. Such fun.

    In our final year we were also on the editorial committee of the school magazine with Iain as editor – early evidence perhaps of his future career.

     A few years ago I sent him a copy of a book written about Wishaw High School in which an article written by Iain about a school holiday to Spain appeared. I quote “ London at 7am is a particularly dreary place and the attempts of some of our party to locate Carnaby Street proved fruitless – although the profusion of miniskirts did bring a contemplative gleam to the eyes of those who study the wonders of nature” and another “It was the one and only time the inhabitants of Callella saw one of their straw hats decked with an SNP badge. {This was 1968} Bemused Spaniards who asked who or what the SNP was were mischievously informed that it stood for “the Shotts Nazi Party”. Shotts is a town in Lanarkshire which used to have significant coal mining around it.

    I was not on that Spanish trip but the previous year he and I were part of a trip to the Italian town of Cavi di Lavagna, not far from Genoa. I think that might have been where our mutual interest in wine began although I think our tastes and palates improved thereafter.

    Iain’s love of travel started then and continued thereafter. His love of geography also started at school and he was winner of the inaugural Archie Leitch Prize for Excellence in Geography in 1967. A prize named after the head teacher of geography who had died in 1966.

    After leaving school we both went to Glasgow University, he to study geography and me to medicine. We tried to meet up every week in the Students Union, particularly to watch the Freds – the Tom & Jerry cartoons produced by the legendary Fred Quimby.

    When our undergraduate careers were over our paths diverged. I went to work in the NHs and Iain went off to Simon Fraser University and then to work for various publishing companies and the Stationery Office before academia took its hold at City University and then UCL. Interestingly the name of the publishing company which Iain founded was also the name of one of the “houses” in our school. We corresponded many times and I much enjoyed receiving blue airmails from him from Canada and also letters when he was living in France for his PhD thesis. We met when we could, not as often as we would have liked admittedly, in London or Bishop Stortford or when he came to Scotland.

    The key thing was that when we met up at any time or corresponded, it was as if we had only seen each other the previous week. We just picked up where we left off – the essence of true friendship. I will cherish that for the rest of my life.

    He was warm and friendly, witty and funny and a font of knowledge on many different subjects. From other tributes I have read, he was an inspiration to many. To me he was a true friend for 55 years.

    The wee pit boy frae Shotts did well." Hector Campbell, Retired Consultant Surgeon.

  • "It was sad to hear of Iain’s death. As a fellow philatelist we would often chat over a cup of tea at meetings of the Royal Philatelic Society London. We shared a common interest in so-called Cinderella stamps, such as those of the Oxford and Cambridge colleges or the telegraph companies. Iain was a font of knowledge on these as on so many other things, and a delightful companion." Vincent West FRPSL