“…Blocksma and Porter (1947), Carkhuff and Truax (1965), and later Burck, Jacobs, Sauber, Stone, and Thomson (1973), Delaney, Long, Masucci, and Moses (1969), Emener (1973), and Redfering (1973) have demonstrated that IDET generates significant increases in trainees' abilities to communicate FC to clients. Several investigations have shown that between 1 and 100 hours of IDET is significantly more effective than no training (Ashworth, 1971;Berenson et al, 1966;Brockhaus, Marshall, & Dustin, 1973;Butler & Hansen, 1973;Dooley, 1975;Pacoe, Naar, Guyett, & Wells, 1976;Selfridge et al, 1975;Shapiro & Gust, 1974), placebo-control didactic lectures (Gormally et al, 1975;Martin & Carkhuff, 1968), an equivalent amount of "traditional" clinical or counseling training (Carkhuff, Kratchovil, & Friel, 1968;Leitner, 1973;Rye, 1970;VanderKolk, 1973), or an equivalent amount of "experiential" training (Berenson et al, 1966;Rye, 1970).…”