Mindfulness is typically described as a form of nonjudgmental, nonreactive attention to experiences occurring in the present moment, including cognitions, emotions, and bodily sensations, as well as sights, sounds, smells, and other environmental stimuli. The cultivation of mindfulness is a central component of Eastern meditation traditions and lies at the heart of Buddhist teachings about the nature of reality and human experience. This chapter argues that mindfulness cultivates human characteristics that are central to positive psychology, including character strengths and virtues and psychological well-being, but it does so through acceptance-based rather than change-based methods. Because mindfulness training appears to have a broad range of outcomes, including enhancement of positive characteristics, its potential contribution to optimal human functioning warrants substantially increased attention. The chapter examines the literature supporting this view, discusses the processes or mechanisms through which this may occur, and suggests directions for future research.