Numerous investigations have sought to understand the types of individuals who engage in post-retirement work. However, little is known about why older adults are motivated to engage. The aim of the present article is to examine the extent to which two possible mechanisms—adaptation (adjusting to the loss of work role) and exploration (retirement as opportunity to engage in activities in line with personal values)—play a role in explaining planning for paid work or volunteering after retirement. Analyses are based on large-scale survey data collected in 2015 among older workers in the Netherlands (N = 6,278). Results show that the large majority of older Dutch workers have plans for post-retirement paid and/or volunteer work. Moreover, both mechanisms appear to contribute to the understanding of post-retirement work plans, yet in different ways. Specifically, older workers who expect to miss latent work functions are more likely to have plans for post-retirement work, with their general values guiding the type of work they gravitate toward. Having plans for post-retirement paid work was more prevalent among older workers who attached more importance to personal growth, whereas having plans for volunteer work was more prevalent among older workers who had a stronger social orientation. Moreover, results suggest that men, more often than women, translate the anticipated loss of latent work functions into plans for post-retirement paid work. These insights regarding the motivational antecedents of post-retirement work plans are highly relevant in light of policy discussions of active and healthy aging.