How have men become gay fathers and how have their decisions about parenthood shaped their experiences? In this study of 739 gay fathers from across the United States, we explored generational changes in timing of parenthood and its association with identity development, sexual orientation disclosure, and social support. In this sample, most men over 50 years of age, but only a minority of younger men, reported that they had fathered children in the context of heterosexual relationships. In contrast, few of those over 50, but most of the younger men, reported that children joined their family in the context of a same-sex relationship. Moreover, timing of parenthood was the strongest predictor of the fathers' experiences of sexual identity development, disclosure, and social support. The findings are consistent with the idea that a generational shift is underway and that this shift has important implications for gay fathers' experiences.