Depression is associated with profound personal and societal costs worldwide, in great part due to negative functional and psychosocial consequences. These consequences can range from minimally disruptive to life-altering, and they occur across a wide variety of life domains (e.g. home, work, school, social). Despite patient preference for the inclusion of functional outcomes as the desired endpoint of antidepressant treatment and goal for the achievement of wellness, functional outcomes are still infrequently measured. This is likely due, at least in part, to the wide variety of assessment tools that are available and lack of consensus definitions of functional recovery. This chapter reviews several measures that are available to assess functioning; describes the functional impairment associated with depression and related symptoms, such as cognition, sleep, and pain; and briefly discusses issues associated with treating disrupted functioning in depression. Future directions include the need to develop and utilize a consensus definition of functional recovery, as well as consistent incorporation of functional assessment in both clinical monitoring and research outcomes.