We thank the following people for their valuable comments and other contributions that have helped us to develop the second edition of Testing Treatments:

Claire Allen, Doug Altman, Patricia Atkinson, Alexandra Barratt, Paul Barrow, Ben Bauer, Michael Baum, Sarah Boseley, Joan Box, Anne Brice, Rebecca Brice, Amanda Burls, Hamish Chalmers, Jan Chalmers, Yao-long Chen, Olivia Clarke, Catrin Comeau, Rhiannon Comeau, Katherine Cowan, John Critchlow, Sally Crowe, Philipp Dahm, Chris Del Mar, Jenny Doust, Mary Dixon-Woods, Ben Djulbegovic, Iain Donaldson, George Ebers, Diana Elbourne, Murray Enkin, Chrissy Erueti, Curt Furberg, Mark Fenton, Lester Firkins, Peter Gøtzsche, Muir Gray, Sally Green, Susan Green, Ben Goldacre, Metin Gülmezoğlu, Andrew Herxheimer, Jini Hetherington, Julian Higgins, Jenny Hirst, Jeremy Howick, Les Irwig, Ray Jobling, Bethan Jones, Karsten Juhl Jrgensen, Bridget Kenner, Debbie Kennett, Gill Lever, Alessandro Liberati, Howard Mann, Tom Marshall, Robert Matthews, Margaret McCartney, Dominic McDonald, Scott Metcalfe, Iain Milne, Martin McKee, Sarah Moore, Daniel Nicolae, Andy Oxman, Kay Pattison, Angela Raffle, June Raine, Jake Ranson, James Read, Kiley Richmond, Ian Roberts, Nick Ross, Peter Rothwell, Karen Sandler, Emily Savage-Smith, Marion Savage-Smith, John Scadding, Lisa Schwartz, Haleema Shakur, Ruth Silverman, Ann Southwell, Pete Spain, Mark Starr, Melissa Sweet, Tilli Tansey, Tom Treasure, Ulrich Tröhler, Liz Trotman, Liz Wager, Renee Watson, James Watt, Hywel Williams, Norman Williams, Steven Woloshin, Eleanor Woods, and Ke-hu Yang.

Iain Chalmers and Paul Glasziou are grateful to the National Institute for Health Research (UK) for support. Paul Glasziou is also grateful to the National Health and Medical Research Council (Australia).

And a special thank you to our publisher, Martin Wagner, of Pinter & Martin for his forbearance, cheerful encouragement, and cool head at all times.