One of the main transformations of medical practice in the last quarter of a century is the meteoric growth of evidence-based medicine (EBM). The name of this new movement, may sound like a provocation, since it implies that before the advent of EBM in the 1980s medical decisions, especially those related to therapy, were not based on sound evidence. However, from the mid-nineteenth century, doctors repeatedly claimed that medicine had became a scientific discipline, a claim reiterated and reinforced in the twentieth century. Moreover, the main tool employed by EBM, the randomized controlled trial (RCT), is not a recent invention: it was developed in the 1940s, and became increasingly popular in the post-Second World War era, partly because regulatory agencies increasingly required that the efficacy of a new drug should be proved in an RCT, before issuing a marketing permit. On the other hand, the growing accumulation of results of controlled clinical trials did not seem to affect standards of routine clinical care. Left to their own devices, few doctors relied on the critical evaluation of RCT's in their clinical decisions. Physicians continued to gather information in a haphazard way, to draw general conclusions from personal experience, and to listen to representatives of the pharmaceutical industry. The founders of the EBM movement—a group of clinical epidemiologists from McMaster University in Canada under the charismatic leadership of David Sackett—decided to make reliable information on therapies available to all clinicians, a task facilitated by the development of computers and of the Web. The McMaster initiative was exceptionally successful. Today we have numerous EBM publications, internet sites, and decision tools. EBM courses are included in the curriculum of the majority of medical schools, and the new generation of physicians will probably “talk EBM” as naturally as Moliere's Mr Jourdain spoke prose. In parallel, EBM generated strong opposition and provoked heated debates. The latter are, however, confined to a specialized press: the growing importance of EBM has low visibility beyond the esoteric circles of experts. Daly's book, the first comprehensive history of EBM, therefore, fills an important gap. Daly started by writing the history of clinical epidemiology (one of the domains that led to the development of EBM), then enlarged her project to include the history of evidence-based medicine, and of a similar initiative, the Cochrane Collaboration, developed in Great Britain by Iain Chalmers. She produced a detailed and thorough study, grounded in numerous interviews and observations. One of her key findings is the great heterogeneity of uses of EBM. The sociologists Stephan Timmermans and Mark Berg investigated the variety of these in a single clinical setting. Daly focuses on the role of local and national variables in modulating the uses of clinical evidence in different sites. She illustrates her point through a detailed study of Cochrane Collaboration in South Africa. Daly's book also provides a critical perspective on EBM and shows the limitations of approaches that focus on RCT's and fail to incorporate contributions of disciplines such as classical epidemiology or public health. Evidence-based medicine and the search for a science of clinical care does not cover all aspects of the history and present development of EBM. Some areas—such as the role of state policies—are mentioned only briefly, while others—such as the impact of the pharmaceutical industry—are, regrettably, absent. Daly's pioneering work is, nevertheless, an important contribution to the understanding of EBM and thus of recent changes in clinical practice. It is highly recommended to all those who want to understand what is truly new in today's medicine.