As physical activity decreases with age, it is important to examine what motivates older adults to walk their dog(s). Interviews with 17 retired adults (>= 65 years) were guided by Organismic Integration Theory and Basic Psychological Needs Theory and were coded using Braun and Clarke’s (2013) thematic analysis to develop themes. Motivations for dog-walking were more frequently regulated through intrinsic, integrated, or identified regulation than through introjected, external, or non-regulation. Several main themes emerged. For autonomy, they were negotiating needs, choosing to give the dogs autonomy, exchanging exercise for dog-walking, and retiring. For relatedness, they were meaningful interactions, strengthening friendships, building community, and attachment to their dog. For competence, they were regaining and maintaining competence, challenges to competence, and high physicality and frequent walking as baseline. These results suggest dog-walking may be more intrinsically motivated and help satisfy the three basic psychological needs for retired adults aged >= 65.