The learning disabilities literature of the past 15 years pertaining to sex differences is reviewed, including prevalence in children, socialization effects, physiological vulnerability, family patterns, differing expectations of parents and teachers, and differing patterns of response to failure. Analysis of data obtained over the last 2 years on 210 boys and 210 girls aged 5 to 18 shows the learning disabilities characteristics of both boys and girls to be clinically similar, but more girls (56%) than boys (39%) were below grade level in basic skills, particularly comprehension (35% compared to 17%). However, a considerably larger percentage of boys (53%) than girls (33%) were receiving services in their schools. More girls (78%) than boys (48%) showed personality styles characterized by constriction, separation anxiety, passivity, and withdrawal, while more boys (45%) than girls (18%) were described as being impulsive, aggressive, belligerent, defiant, and oppositional. The survey results underline the importance of distinguishing, insofar as is possible, a psychoneurologically-based learning disability from a general pattern of passivity, helplessness, and lack of achievement motivation, or combination. Increased concern regarding learning problems and achievment for girls has paralleled social changes. Girls in need of evaluation and help with learning problems are being identified at an increasing rate. Although learning-disabled girls may be fewer in number, it is suggested that their access to services should be equal. (Author/CL)