Individual marital therapy (IMT) is therapy in which one or both spouses are treated separately by different therapists who do not communicate with each other about treatment. Gurman and Kniskern (1978) reported an improvement rate of 48% and a deterioration rate of 11.6% for nonbehavioral IMT. These outcome data and the conclusions drawn from them have precipitated oppositional reappraisals and critiques, notably by Jacobson (1978) and by Wells and Gianetti (1986). Jacobson disregarded Gurman and Kniskerns' outcome research on grounds of its generally inferior research design and methodology. Wells and Gianetti reappraised each of the original studies by Gurman and Kniskern and concluded that the studies had major flaws of design and implementation. This controversy may be resolved by: (1) examining reported efficacy rates for nonbehavioral IMT; (2) describing evaluations and interpretaions of the data; (3) explaining why alternative interpretations and explanations are given for the same outcome research; and (4) presenting an original critique and evaluation of the debate on IMT outcome research. Completion of these four steps suggests that the 1978 appraisals by Gurman and Kniskern of the improvement and deterioration rates for nonbehavioral IMT were based on studies which do not meet minimum requirements for outcome research. To date, there is little acceptable empirical evidence either for or against the efficacy of IMT. The exploration and generation of investigative questions on this issue, however, should be seen as a valuable and worthwhile endeavor. A seven-page list of references concludes the paper. (NB)