This is author-approved bcc: The papers in this volume were contributed in honor of Lucien Le Cam on the occasion of his 70th birthday. They reflect the immense influence that his work has had on modern statistics. The papers include discussions of Le Cam's seminal ideas, historical perspectives, and contributions to current research. They reach back two centuries, with a new translation of a paper of Daniel Bernoulli, and they reach forward to new ideas about semiparametric theory and wavelets. The volume begins with the paper of Aalen, which describes Le Cam's role in the founding of the martingale analysis of point processes, and ends with the paper of Yu, which explores the position of just one of Le Cam's ideas in modern semiparametric theory. The other 27 papers touch on other areas-such as local asymptotic normality, contiguity, efficiency, admissibility, minimaxity, empirical process theory, and biological medical, and meterological applications - where Le Cam's insights have been the foundations on which a theory has been built.