To investigate changes in scholarly influence in criminology and criminal justice over 20 years, the most-cited scholars in six major American journals were determined for 2001-05, and the results were compared with those obtained for 1996-2000, 1991-95, and 1986-90. The most-cited scholars in 2001-05 were Robert J. Sampson in American criminology journals and Francis T. Cullen in American criminal justice journals. Highly cited scholars in American criminology journals focused on longitudinal/criminal career research and/or criminological theories, while those in American criminal justice journals focused on these topics or on criminal justice issues. Some highly cited authors were specialized, with one or two highly cited major works, while others were versatile, with many different works cited a few times each. Over time, older scholars such as Marvin E. Wolfgang were cited less often, while younger scholars such as Robert J. Sampson were increasingly cited. The waxing and waning of criminological influence careers are documented.In order to investigate scholarly influence in criminology and criminal justice (CCJ), Cohn and Farrington (1994b) investigated the most-cited scholars in six major American CCJ journals during the time period 1986-90. They repeated this analysis to assess the most-cited scholars in these journals during 1991-95 (Cohn and Farrington 1998a-2000(Cohn and Farrington 2007. The purpose of the present article is to repeat this methodology once again to assess the most-cited scholars between 2001 and 2005, and to draw conclusions about changes in cited authors over this 20-year time period. Specifically, the aim is to identify which scholars are becoming more or less highly cited, as well as to examine the most-cited works of the most-cited scholars. This helps to document the waxing and waning of scholarly influence in criminology over time.