Effective agency, according to contemporary Kantians, requires a unity of purpose both at a time, in order that we may eliminate conflict among our motives, and over time, because many of the things we do form part of longer-term projects and make sense only in the light of these projects and life plans. Call this the unity of agency thesis. This thesis can be regarded as a normative constraint on accounts of personal identity and indeed on accounts of what it is to have the life of a person in the broad, rather than narrowly biological sense. It is also a fundamental condition of social life that persons within society fulfill a range of longitudinal roles: parenthood is one such obvious example, as are teachers, health professionals, engineers, artists, and many others. The fulfillment of these and other valuable social roles requires that agents have the capacity to rationally conceive of themselves as engaged in these roles and subject to the demands of them. To be unable to fulfill any such longitudinal social roles is to have a life deficient in value. The unity of agency is thus, we argue, something we rationally strive for, and something to be morally promoted. Psychiatric states that undermine the unity of agency are morally and rationally disvaluable. Using the example of dissociation, we explain how one such state may have this undermining or disruptive effect on the unity of agency. The therapeutic ends for psychiatry in conditions involving such states are thus seen more globally as the restoration of effective agency, that is, unified agency.