Accurate density and population estimates are needed to manage bear populations but are difficult to obtain. Most such estimates reported for bears are largely subjective and lack estimates of precision. Fifteen brown bear (Ursus arctos) and 3 black bear (U. americanus) density estimates were obtained in Alaska during 1985 through 1992 using 2-9 replicates of capture-mark-resight (CMR) techniques in 17 different areas. Our studies used radiotelemetry to document movements of marked animals into and from search areas. This procedure essentially eliminated the need to correct density estimates for edge or periphery effects caused by absence of geographic closure. To estimate population size, we used a maximum-likelihood estimator modified to accommodate temporary movements of marked animals into and from our search areas. Our approach permitted direct calculations of density from our population estimates. Our procedures provided density estimates that were repeatable, were comparable among areas, included estimates of precision, and were more objective than methods historically used to estimate bear abundance. Our density estimation procedures have widespread applicability for other wildlife studies using radiotelemetry. Our estimates were obtained within a wide spectrum of habitats and provided a range of Alaskan densities from 10.1 to 551 brown bears (all ages)/1,000 km 2 and from 89 to 289 black bears (all ages)/1,000 km 2 . Our highest brown bear density is probably near the maximum for this species, but areas with lower densities (3.9/1,000 km 2 ) have been reported in Alaska. Areas with black bear densities higher than in our study areas probably occur in Alaska. Brown bear densities were 6-80 times greater in coastal areas where abundant runs of multiple species of salmon (Oncorhynchus spp.) were available to bears than in interior areas. Our CMR technique provided useful data for bear population management and impact assessments and has potential for application to other species and areas.