Presents a brief explanation of implosive theory and technique and critically reviews the case reports and experimental investigations of implosive therapy and flooding procedures with human Ss. Much of the research has produced confusing and contradictory results, and these findings are discussed in terms of the type of response rehearsed in therapy, exposure time, and cognitive factors. It is concluded that there is, at present, no convincing evidence of the effectiveness of implosion or flooding with human Ss, nor is there any evidence that the techniques are superior to systematic desensitization. In addition, the theoretical basis of implosive therapy appears to be unsupported. Finally, serious realistic and ethical questions are raised in regard to the desirability of the clinical use of implosive procedures. (78 ref.) (PsycINFO Database Record (c) 2012 APA, all rights reserved)