Mindfulness is an ancient practice, derived from Buddhism and recently adapted for the treatment of depression and other psychological conditions. The mechanism of action is thought to involve the extinction of habitual or conditioned responses to internal cognitive and emotional content. In turn, this relies on mechanisms of attentional control and emotion regulation. The resulting state of consciousness is sometimes described as equanimity. This conceptual review paper explores the process of achieving equanimity within a homeostatic framework. The result is a model of moodfulness, which combines mindfulness with Homeostatically Protected Mood to provide a new theoretical view of recovery from symptoms of depression. This model presents a case for mindfulness restoration of mood homeostasis following homeostatic defeat.