"Coping flexibility" was defined as the ability to discontinue an ineffective coping strategy (i.e., evaluation coping) and produce and implement an alternative coping strategy (i.e., adaptive coping). The Coping Flexibility Scale (CFS) was developed on the basis of this definition. Five studies involving approximately 4,400 Japanese college students and employees were conducted to test the hypothesis that flexible coping produces more adaptive outcomes. Studies 1, 2, and 3 provided evidence of the reliability of the CFS scores as well as of its convergent and discriminant validity for Japanese samples. Study 4 further demonstrated that flexible coping was positively associated with improved psychological health, including reduced depression, anxiety, and distress. In Study 5, coping flexibility as measured by the CFS was associated with reduced future depression, even after controlling for the effects of other coping flexibility measures and popular coping strategies. Overall, these results suggest that a valid approach for assessing coping flexibility has been developed and that flexible coping can contribute to psychological health. The implications of these findings for clinical practice are discussed. (Contains 3 footnotes and 4 tables.)