“…The literature on the effectiveness of flooding techniques is more mixed than that of systematic desensitization, partly due to the confounding of flooding with implosive therapy, which involves imaginal exposure to extreme and unrealistic stimuli (Morganstern, 1973; Smith, Dickson, & Sheppard, 1973). Some studies have demonstrated the relative effectiveness of flooding over systematic desensitization (Boulougouris, Marks, & Marset, 1971; Marks, Boulougouris, & Marset, 1971; Marshall, Gauthier, Christie, Currie, & Gordon, 1977; see Smith, Dickson, & Sheppard, 1973 for a review), while others have reported mixed results and raised ethical concerns over the use of flooding in anxious clients (Morganstern, 1973). Concerns have also been raised about clients’ acceptability of flooding.…”