24 snake phobic Ss participated in an experimental investigation of systematic desensitization therapy. Ss who experience desensitization showed a greater reduction in phobic behavior (as measured by avoidance behavior in the presence of the phobic object and self-ratings) than did nonparticipating controls. Ss tended to hold or increase therapy gains at a 6-month follow-up evaluation, and gave no evidence of symtom substitution. (PsycINFO Database Record (c) 2006 APA, all rights reserved)