The purpose of this study was to examine relationships between personality traits (conscientiousness, extraversion, and neuroticism), self-determination, self-efficacy for exercise and perceived health to the stages of exercise behavior change (SEBC) and to identify relationships between personality traits (conscientiousness, extraversion, and neuroticism) and self-determination (amotivation, external, introjected, identified, and intrinsic regulation) among regular exercisers. Subjects were a convenience sample of 188 older adults (mean age = 71.1, SD = 8.5) living in a Midwestern community. Questionnaires included the NEO-Five Factor Inventory (NEO-FFI), the Behavioral Regulation for Exercise Questionnaire (BREQ-2), the Stages of Exercise Behavior Change (SEBC), the five item Self-Efficacy Questionnaire (SEQ), 12-Item Short Form Health Survey Instrument (SF-12), and Physical Activity Scale for the Elderly (PASE). Data were analyzed using descriptive statistics, ordinal logistic regression utilizing Proc CATMOD & Proc GENMOD and one-way ANOVA. Results showed that education was correlated with SEBC. Proc CATMOD showed that of 10 predictor variables, conscientiousness, overall self-determination, self-efficacy for exercise, perceived mental health and perceived physical health were positively associated with SEBC. Proc GENMOD identified that intrinsic regulation and self-efficacy for exercise distinguished the precontemplation stage; conscientiousness and introjected regulation distinguished the preparation stage; introjected regulation and perceived physical health status distinguished the action stage; and conscientiousness, introjected regulation, intrinsic regulation, perceived mental health status and self-efficacy for exercise distinguished the maintenance stage. Among those in the maintenance stage (n=128) extraversion was positively correlated with intrinsic regulation and conscientiousness was positively correlated with identified regulation and intrinsic regulation. In addition, overall PASE scores were significantly different across SEBC. Older adults in the maintenance stage were more engaged in strenuous sport, recreational activities, muscle strength and endurance activities than those in the precontemplation, contemplation, and preparation stages. These findings should be considered in the process of developing effective stage-based intervention strategies among older adults in order to increase the probability of moving from a lower to a higher stage and then maintaining the stage shift.