A prominent call in this paper is for more in-depth, descriptive research into the longitudinal patterning of criminal careers, as well as a renewed call for more current data sources that contain the necessary information to assess contemporary incapacitation effects. Questions and answers about incapacitation abound in all discussions about criminal justice policy. They are among the most pressing of all research issues, yet estimates about the incapacitation effect on crime vary considerably, and most are based on very old and incomplete estimates of the longitudinal pattern of criminal careers. This paper has three principal aims. First, to present a brief overview of the main issues regarding the incapacitation literature that is concerned with estimation of individual offending rates. The second is to highlight some recent criminal career findings that illuminate the importance of such information and its relevance for generating incapacitation estimates. Lastly, the paper presents an argument for the criminological approach and sets an agenda for future research that seeks to further the knowledge base about the incapacitation effect. References