Over the past half century, psychotherapy research has demonstrated that psychotherapy outcomes do not vary based on clients' gender (Clarkin & Levy, 2004; Garfield, 1994; Wierzbicki & Pekarik, 1993). However, most studies assumed that all psychotherapists are equally competent to treat men and women, thus potentially missing essential information about variations in psychotherapy outcomes. In fact, there is a paucity of studies that have examined if psychotherapists' gender competence truly exists. We propose that psychotherapists' gender competence should be defined as the psychotherapist's ability to achieve positive psychotherapy outcomes with either female or male clients. This study examined the relationship between clients' gender and psychotherapy outcomes and if psychotherapists varied in their abilities to produce positive psychotherapy outcomes for female and male clients. The sample included 93 male and 229 female clients treated by 31 psychotherapists. Consistent with previous research, the results demonstrated that clients' gender was not related to psychotherapy outcomes. However, compared to other psychotherapists, some psychotherapists were better at treating men, whereas others were better at treating women. The results of this study demonstrate that psychotherapists' gender competence exists and relates directly to the psychotherapy outcomes (i.e., psychological well-being) of clients. Implications for psychotherapy practice, training, and research are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved).