Marital stress, strain, and coping strategies were investigated in chronic pain patients by administering the Problems of Everyday Life Interview (PEL) to 55 married chronic pain patients. Subjects were assigned to either limited, moderate, or heightened mastery groups based upon PEL mastery scores. The heightened mastery group reported less marital strain, less marital stress, more use of negotiation, less use of selective ignoring, and less use of manage-stress coping strategies than either limited mastery or moderate mastery groups. There were no significant differences between limited mastery and moderate mastery groups on any variables measured. There were no differences between mastery groups on advice seeking. The effects of mastery as a mediator of coping and stress are discussed, as well as the advisability of incorporating treatments that specifically address feelings of lack of control over stressful events into chronic pain programs, especially when marital problems are identified.