The systematic, comprehensive review covered 126 articles published during 1989-94 in nine primary journals, which were identified through PsychINFO of the American Psychological Association as publishing the greatest number of articles on child abuse during this period. The analysis revealed that adult males are dramatically underrepresented in this research. Males were included in only 47.7 percent of the 77 articles reviewed, and the total number and percentage of males in research samples was significantly less than the number and percentage of females. Only three studies included only males, while 40 studies involved only females. Only 37.5 percent of the studies that did include men provided an evaluation of gender differences. Research involving abused children had a much greater representation of male participants than did research with adults participants. Only four of 49 studies of abused children were based exclusively on females, while 62.8 percent included an equal representation of males and females. Findings indicated the need to increase the inclusion of males in research samples to obtain a comprehensive understanding of the causes and consequences of physical abuse and to improve prevention and treatment models for abusive parents and abuse victims. Tables and 11 references (Author abstract modified)