Compassion is often described in terms of suffering. This paper investigates the nature of this suffering. It is argued that compassion involves suffering of a particular kind. To begin with a case is made for the negative claim that compassion does not involve an ordinary, or afflictive, suffering over something. Secondly, it is argued that the suffering of compassion is a suffering for someone else’s sake: If you feel compassion for another person, P, then you suffer over P:s suffering for P:s sake, and if that is all you do, then you are not affected with an afflictive suffering over something. The final section identifies and addresses a problem concerning self-pity, and a suggestion is made on how to specify the proposed account so as to cover both self-directed and other-directed compassion.