We review recent research to establish that the associations between positive emotional experience and major forms of psychopathology show considerable specificity. Although indicators of low positive affect are consistently related to both social anxiety/social phobia and schizophrenia/schizotypy, they are more strongly linked to depression, thereby displaying relative specificity. Moreover, low positive affect actually shows greater specificity than the diagnostic criteria for depression and is most strongly related to those symptoms (anhedonia, dysphoria, lassitude, suicidality) that are specific to the disorder. With regard to social phobia, findings suggest that low positive affect is more strongly related to the generalized subtype than to the non-generalized performance subtype. Analyses of schizophrenia/schizotypy indicate that although low positive affect is consistently associated with the negative symptoms (e.g., constricted affect, social aloofness), it is only weakly related to positive symptoms (e.g., magical thinking, perceptual aberrations, suspiciousness). Other data suggest that schizophrenia is associated with an anticipatory pleasure deficit, such that individuals with the disorder engage in rewarding activities less frequently because they do not expect to derive pleasure from them. Finally, we summarize evidence indicating that elevated positive affect is both a risk factor for bipolar disorder and a concomitant of manic symptoms.