In this article, we examine subjective vitality, a positive feeling of aliveness and energy, in six studies. Subjective vitality is hypothesized to reflect organismic well-being and thus should covary with both psychological and somatic factors that impact the energy available to the self. Associations are shown between subjective vitality and several indexes of psychological well-being; somatic factors such as physical symptoms and perceived body functioning; and basic personality traits and affective dispositions. Subsequently, vitality is shown to be lower in people with chronic pain compared to matched controls, especially those who perceive their pain to be disabling or frightening. Subjective vitality is further associated with self-motivation and maintained weight loss among patients treated for obesity. Finally, subjective vitality is assessed in a diary study for its covariation with physical symptoms. Discussion focuses on the phenomenological salience of personal energy and its relations to physical and psychological well-being.