Questions regarding the efficacy of psychotherapy and the relative merits of different types of therapeutic modalities have been asked for decades. In the first comprehensive review of the efficacy of different therapeutic models, Smith, Glass, and Miller (1980) conducted a meta-analysis of available outcome data. Their generally positive conclusions about the efficacy of psychotherapy none the less revealed serious limitations in the available evidence, and some disparity in the difference in outcomes comparing the most to the least successful of different therapy approaches. It is notable that Smith, Glass, and Miller (1980) have been followed by other meta-analyses of various treatment approaches, and with various clinical problems (e.g., Dobson, 1989; Miller & Berman, 1983). There is now ample evidence to support the claim that psychotherapy is effective in general, even while the research accumulates about the relative outcome of different therapy approaches for specific clinical disorders or conditions.