A study is described that provides a methodological model for testing theoretical constructs and investigating pragmatic social problems simultaneously. Behavioral and attitudinal consequences of viewing erotic films are assessed in terms of cathartic, instigational, and social learning formulations. Comparative attitudinal and behavioral changes over a twelve-week period are reported for 51 married couples who viewed erotic films, 17 couples who viewed nonerotic films, and 15 couples who viewed no films. All couples who viewed films completed 84 consecutive daily checklists of sexual and marital behavior. Couples viewing erotic films reported significantly more sexual activity on film viewing nights, and became more tolerant of legal exhibition of erotic films. No group exhibited significant stable changes in sexual behavior, and completing daily checklists appeared to facilitate sexual activity more than viewing erotic films. Results appear most concordant with social learning theory and fail to support the position that viewing erotic films produces harmful social consequences.