Résumé
Thanks to the progress of the methodology for survival analysis of capture± mark± recapture data, today biologists become able to test the individual or environm ental factors that are likely to affect survival and, relatedly, they can estimate survival with a model that describes satisfactorily and ef® ciently the population and the experiment. Assessment of ® t, adjustment and model selection are the main tasks in the process. Several computer programs exist with complementary abilities in those respects and, most often, one must use successively several of them in a single analysis. As there is no standardized presentation of the data, the transition from one program to another is not particularly easy. C R is a software package that intends to alleviate those dif® culties by putting together some of the most popular programs and providing passageways between them. W e explain how a typical analysis is carried out with CR and insist on thē exibility that can be achieved with SURGE , a program for designing and ® tting survival models which is an integral part of CR. A real example is treated for illustration.