This book takes a novel approach by highlighting comparative and long-term historical perspectives on experimental practice. The juxtaposition of accounts of natural, social, and medical experimentation is very enlightening, especially because the authors put the emphasis on the different kinds of objects of experimentation (physical matter, chemical reagents, social groups, organizations, sick individuals, archeological remains) and demonstrate how much the kinds of objects matter for the practice of experimentation, its methods, tools, and methodologies. Taken together, the chapters raise several fascinating questions for further study: What do these different approaches have in common? Why do we call them “experimentation”? What are the intersections among the fields and their developments? The volume engages philosophical approaches that are not well known to Anglophone readers (Bachelard, Bergson, Bernard, Canguilhem, among others) and brings to attention a wealth of Francophone secondary literature on past and present scientific experimentation. The collection fills a yawning gap in science, science studies, and philosophy of science teaching, making it particularly valuable philosophers and historians of science in all subfields.