This paper describes a new theoretical model of subliminal psychodynamic activation (SPA) effects. The model conceptualizes subliminal-supraliminal differences in SPA effects as being due to differences in subjects' attributions for the changes in anxiety level that are produced by subliminal versus supraliminal SPA stimuli. Changes in anxiety level produced by supraliminal SPA stimuli can be attributed by subjects to the experimental procedures, diminishing the impact of these messages on subjects' responses. In contrast, subjects cannot attribute changes in anxiety level produced by subliminal SPA stimuli to the experimental procedures. Therefore, no “discounting” (i.e., situational) attributions for sublimmafly induced changes in anxiety levels are available to subjects, and subliminal SPA messages produce significantly stronger effects on responding than do supraliminal SPA messages. The attributional model of SPA effects is discussed in the context of other long-term research programs investigating subliminal phenomena. The implications of this model for clinical treatment and empirical research utilizing the SPA paradigm are discussed.