The objective of this longitudinal study was to determine the feasibility of a model for disseminating community-based strength training programs for older adults through leadership training of laypersons or “peers” and health and fitness professionals. The intervention consisted of a progressive strength training, balance, and flexibility exercise program and a leader training and certification workshop. Feasibility was defined as 75% or more of individuals who completed leader training establishing or teaching at least two 12-week strength training classes within 1 year. Program dissemination was quantified as the number of classes established between January 2005 and December 2006. Demographic characteristics and health status of leaders and program participants were evaluated. Two hundred forty-four leaders (peers, n=149; professionals, n=95) were trained and certified. Seventy-nine percent of all leaders (n=193) met the feasibility criteria of establishing or teaching strength training classes. There was no difference in the percentage of peer leaders (80%, n=119) and professional leaders (78%, n=74) who established or taught classes (P=.71) despite significant differences in their demographic and health profiles. Ninety-seven self-sustaining strength training classes were established in senior and community centers, and 2,217 older adults (women, n=1,942; men, n=275) aged 50 to 97 with multiple chronic medical conditions enrolled. In conclusion, training peer and professional leaders is a feasible and successful model for disseminating a community strength training program for older adults. Widespread dissemination of this program has significant public health implications for increasing physical activity participation by older adults.