Children spend considerable time in gender-segregated friendship groups in which they develop gender-typed interpersonal styles that have implications for their adjustment and ability to interact with the other sex. However, most of what we know about gender and friendships comes from studies that included girls and boys but were designed to address other questions. Accordingly, studies such as those in this special issue that were specifically designed to examine the role of gender are especially valuable for learning about girls' and boys' friendships. These essays contribute to our understanding of girls' and boys' friendships in terms of structure (e.g., how many friends girls and boys have), content (e.g., how friends interact), and adjustment correlates. These contributions are discussed and suggestions for future research are provided. Suggestions include that future studies (a) work to increase our theoretical understanding of why gender differences in friendship occur, including by taking social cognition into greater account; (b) examine broad age ranges and follow youths over time; and (c) challenge findings about girls' and boys' friendships that are supported by relatively few studies.