Madeleine akrich is a professor at the Centre de sociologie de l'innovation (Mines ParisTech). After being devoted to the sociology of technology for several years, her work has centred on medicine: firstly, on a comparative study of obstetrical practices between France and the Netherlands, and secondly, on internet discussion groups that focus on health problems. More recently, with Vololona Rabeharisoa, she has coordinated a European project on the engagement of patient organisations with knowledge and the transformative effects it has on their form of activism (see the recent special issue of Biosocieties on 'Evidence-Based Activism', 2014).roland Bal is Professor of Healthcare Governance at Erasmus University Rotterdam. His research interests include science-policy-practice relations and governance infrastructures in healthcare. More recently, he has researched the creation of public accountabilities in healthcare, studying the ways in which public service organisations 'organise for transparency' . He currently works with the Netherlands healthcare inspectorate in research projects on regulation and supervision. Roland's focus is on ethnographic, interventionist research methods. Recent publications have appeared in, amongst other journals,