The Twentieth Century Society

Campaigning for outstanding buildings


Initially set up entirely by volunteers, the Society now has one full time and four part-time staff based at our London offices, as well as other people working on a freelance or voluntary basis.


Catherine Croft Director

Catherine has been Director of the C20 Society since 2002, and is Editor of the C20 magazine. She works Monday – Friday.

Catherine read Architecture at Cambridge University, and did an MA in Material Culture & Architectural History in the USA, where she held a fellowship at the Winterthur Museum in Delaware. She has lectured to post graduate building conservation students throughout the UK, and is an alumni of the Architectural Association course. Prior to C20 Society she worked for English Heritage as a buildings inspector in London and the Midlands. Author of a book on Concrete Architecture, Catherine writes on contemporary as well as historic buildings, lectures internationally and  teaches a course on concrete for conservation professionals at West Dean College.

Get in touch

  • 020 7250 3857

Clare Price Head of Casework

Clare Price is the C20 Society’s Head of Casework and works Monday-Wednesday. She is a Chartered Surveyor, and has an MSc in Conservation of the Historic Environment. She is studying for a PhD in Architectural History at Oxford University, researching Inter-war churches.

Clare deals with all church casework and cases in: Bedfordshire, Berkshire, Buckinghamshire, Cambridgeshire, Durham, Essex, Hertfordshire, Northumberland, Oxfordshire, Suffolk, Tyne and Wear, Scotland and the London boroughs of Barnet, Brent, Ealing, Hammersmith & Fulham, Harrow,  Hillingdon, Kensington & Chelsea & Westminster

Get in touch

  • 020 7250 3857

Coco Whittaker Caseworker

Coco works  full -time alongside our Head of Casework Clare Price and deals with cases in Cheshire, Cornwall, Cumbria, Derbyshire, Devon,  Dorset, Gloucestershire, Greater Manchester, Hampshire, Kent, Lancashire, Leicestershire, Lincolnshire, Merseyside, Northamptonshire, Nottinghamshire,  Shropshire, Somerset, Staffordshire, Surrey, Sussex (East & West), Warwickshire, West Midlands, Wiltshire,  Worcestershire, Yorkshire (North, West & South), Wales, and London boroughs except those managed by Clare Price.

She is also currently pursuing a part-time MSt in Building History at Wolfson College, University of Cambridge, specialising in vernacular and 20th-century architecture and writing a thesis on early 20th-century pithead baths in Durham and Northumberland. Her BA was also at Cambridge Uni in History of Art and Architecture.

Get in touch

  • 020 7250 3857

Andrea Crooks Operations Manager

Andrea is responsible for the administration of the Society, deals with general queries and membership issues, and is normally in the office Monday to Thursday. She is an AAT qualified accountant who studied architecture at Edinburgh University. She more recently worked in finance and operational roles for charities including the Almeida Theatre and Union Chapel, a grade 1 listed building.


Get in touch

  • 020 7250 3857

Oli Marshall Campaigns Manager

Oli manages the society’s campaigns, brand and partnerships.

Amassing 10 years experience with iconic British design brands Anglepoise and Tom Dixon Studio, he developed global partnerships and collaborations with the likes of Paul Smith, Margaret Howell and the National Trust.

More recently, he led the successful campaign to revive the historic Crystal Palace Bowl venue (a former Stirling Prize nominee), launching a record-breaking community crowdfunder and winning match funding from the Mayor of London.

He read English at the University of Newcastle and has written on product design, urbanism and community-centric design.

Get in touch

  • 020 7250 3857

Carlos Finlay Office Assistant and Volunteer Caseworker

Carlos began at C20 as a volunteer, working alongside the Casework team to collate research and put together listing applications for buildings across the UK. He has since become a part-time Office Assistant, working with the Operations Manager to oversee the Society’s daily running.

Carlos was awarded the Huntley McDonald Sinclair Prize for his undergraduate performance when he graduated in History of Art and Architectural History at the University of Edinburgh in 2021. He speaks three languages and spent an Erasmus year in Rome, studying the city’s art and architecture. Carlos is fascinated by all aspects of the built environment and can often be seen somewhere in London with a sketchbook in hand.

Honorary Officers and Trustees of the Society

Ian McInnes Trustee & Chairman

Ian Mclnnes is C20 Society’s Chairman since July 2021. He is a retired architect who specialised in working on existing buildings. He has an AA Masters jn Conservation – his thesis was on post-war office buildings in London’s West End – and he contributed a chapter to the most recent C20 Journal ‘Buildings for Business’. He has been a Twentieth Century Society member for nearly 20 years and has served as Hon Events Secretary, Hon Treasurer and, between 2012-17, as Chair of the Casework Committee. He has organised and led a large number of Society visits and events, including the Remembering Gavin Stamp day. He is chair of his IocaI amenity society, the Dulwich Society and had been chair of the Friends of Dulwich Picture Gallery overseeing its merger with its parent organisation.

Catherine Slessor President

As well as being C20 Society’s President since July 2021,Catherine is currently a Contributing Editor to the Architectural Review and was its Editor between 2010 and 2015. She has written for numerous publications, including the Observer, Guardian, Architects’ Journal, Icon and Dezeen. She studied architecture at the University of Edinburgh and was in private practice for a time before defecting into journalism. She also holds a Masters degree in Architectural History and Theory from the Bartlett School of Architecture, University College London. In 2016 she was awarded an MBE for services to architectural journalism.


Mark Eastment Trustee & Convenor of Publications Sub-Committee

Mark is Editorial Director at Yale University Press, London for Art and Architecture, which includes overall management of the Pevsner revisions and distribution and production of the Survey of London series. His main interests are decorative and mid-century British art. He has a good understanding of the current publishing scene, which should help the Society’s forward publishing programme, maintaining its continued academic excellence while perhaps trying to improve its overall profitability. He also carries out work for Ashmolean Publishing Group, Bodleian Publishing Group, Paul Mellon Publishing Group and Decorative Arts Society.

Julia Lane Trustee and Honorary Secretary

Julia worked as a solicitor in commerce and industry, with a focus on contract documentation and corporate governance. Since retiring she has enjoyed furthering a life-long interest in modern architecture, particularly churches.

Carolyn Parmeter Trustee and Honorary Treasurer

Carolyn has been Honorary Treasurer since 2013.  She had a previous stint as a Trustee and Honorary Membership Secretary in the early 2000s.  She has a tax background and is a Senior Civil Servant working in policy at HMRC. Outside work she was a volunteer guide at the National Trust’s 2 Willow Road for over 10 years and for a shorter time at The Homewood.

David Heath Trustee and Chair of Casework Committee

David read architecture at Cambridge University, and has been a registered architect since 1975. Until 2007, he was Chief Conservation Architect at English Heritage. He has had a long involvement with the AA Post-Graduate Course in The Conservation of Historic Buildings, where from 2007 until 2013 he was thesis tutor. From 2010 until 2015 he was Chair of The Society for the Protection of Ancient Buildings (SPAB).


Peter Ruback Trustee and Honorary Events Secretary

Peter is the Society’s Honorary Events Secretary. He was C20 Society Chairman from 2012 to 2021. After a short period as a theoretical physicist he was a civil servant working in central government in a variety of transport policy and housing roles mainly concerned with investment, financing, regulation and planning of infrastructure. He is interested in all styles of post-1914 architecture and is passionate about protecting and reducing the threat to buildings that are easily passed over and not widely appreciated. He also chairs the Westminster Tree Trust and the Pimlico Neighbourhood Forum.

Jane Rosier Honorary Membership Secretary

Jane is a marketing, brand and audiences’ consultant working in the cultural sector. As Head of Marketing at the V&A for 20 years, Jane led the team who transformed the V&A brand into one of the most successful in its sector, and generated record visitor numbers. Previously Jane worked for a number of leading arts organisations including the National Theatre and the Royal Opera House. She is a Member of the Chartered Institute of Marketing and has spoken at numerous conferences on subjects including brand and organisational change, audience research, and both corporate and exhibition marketing campaigns. Jane’s interest in C20th architecture started at a young age with a school visit to Coventry Cathedral.

Cela Selley Trustee

Cela was employed by the Society for 10 years as office co-ordinator, and then developed the role of C20 Volunteering Co-ordinator. She was the Society’s Honorary events Secretary until July 2021.  She is also an elected member of the management team of a successful sports and leisure club, responsible for HR.

Andrew Jackson Trustee & National Groups Coordinator

Andrew studied at Liverpool School of Architecture and the University of Liverpool’s Department of Civic Design and is an architectural historian with a particular interest in urbanism. He has worked with a number of museums and galleries, including as ‘urbanist in residence’ in Sheffield and is a Trustee of Sheffield Design Awards. He was Chair of the C20 Yorkshire Committee from 2014 until 2019 and currently sits on the Casework Committee. His role as National Groups Coordinator involves fostering links with individuals and organisations outside of London and overseeing the activities of the Society’s regional committees, as well as representing them at national level.


John Clarke Trustee

John is a solicitor in private practice and has specialised in the charity sector for many years, advising on charity issues including corporate and charity governance, public benefit, conflicts, employee and volunteer issues. He is a member of the Society’s data management committee dealing with the implementation of privacy and data protection law. John has a lifelong fascination with modern architecture and the protection of buildings under the vagaries of our planning laws.

Ellen Gates Trustee

Ellen worked as a solicitor, specialising in major infrastructure, transport and energy projects.  Since retirement, she has pursued a lifelong, but amateur, interest in architectural history, with an increasing focus on twentieth century architecture.  She also volunteers for the Society, assisting the Caseworkers.

Sarah Jackson Trustee

Sarah has been a registered architect since 1994. After working in architectural practice and teaching history of architecture, she joined CABE, where she was Head of Design Review.  Sarah is currently a townscape and heritage consultant, working on major developments in London.

Dr Alan Powers Trustee

Alan is an architectural historian specialising in British architecture. A founder member of the Thirties Society in 1979, he has filled a number of roles since that time, as caseworker, Honorary Secretary and Chairman. He is joint editor of the Society’s journal, Twentieth Century Architecture, which he founded in 1994, and of the monograph series Twentieth Century Architects. He usually organises the spring and autumn lecture series in London and has led many events.


Otto Saumarez Smith Trustee

Otto Saumarez Smith is Assistant Professor in Architectural History at the University of Warwick. He was Shuffrey Junior Research Fellow at Lincoln College Oxford, and received a PhD from the University of Cambridge. His book Boom Cities, Architect Planners and the Politics of Radical Urban Renewal in 1960s Britain is published with Oxford University Press. He co-edited the Volume 11 of the Twentieth Century Society’s Journal on Oxford and Cambridge. He is a Fellow of the Royal Historical Society, and an editor of the Society of Architectural History of Great Britain’s journal Architectural History. He has published on subjects such leisure centres, inner city policy, shopping centres, as well as architectural practices including Gillespie Kidd & Coia, Chamberlin Powell & Bon, Sheppard Robson, Building Design Partnership, Howell, Killick, Partridge and Amis, and Powell and Moya.


Neal Shasore Trustee

Neal is Head of School at the London School of Architecture. An architectural historian, he has published and lectured widely on twentieth century architectural culture in Britain. His first book, Designs on Democracy: Architecture and the Public in Interwar London will be out in 2022, and he is currently completing a second on the RIBA’s headquarters at 66 Portland Place. He is a passionate advocate of equality, diversity and inclusion in higher education and the built environment.


Image © James Jordan Photography for the London School of Architecture

Website and publications

James Hunter Art Director, C20 Magazine

Jane Anderson Deputy Editor, C20 Magazine

James Hunter & Stephen Coates, & Ebow, the digital agency Web design

James Sui Web developer


Wendy Akers Volunteer press officer

Simon Wartnaby Events volunteer

Joshua Mardell Building of the Month editor

Alexa Baracaia Facebook & Twitter volunteer

Thaddeus Zupančič Instagram volunteer

Joe Austin
Diana Coulter
Ellen Gates
Graham Orbell
Holly Rowland
Casework volunteers

Charles Collett
Matthew Gibbons
Julie Kenwright
Office Volunteer

David Thomas Membership volunteer

Rosemary Clarke
Sarah Lewis
Carolyn Parmeter
Suzanne Waters
Lectures series volunteers

Volunteer your talent

Use your spare time and talents to help us as a valued C20 Society volunteer.

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