This paper derives theoretical mechanisms from differential association theory and social control theory, specifying how broken homes may influence delinquency among both blacks and nonblacks. The analysis specifies a structural equation model of delinquency (Matsueda 1982), derives competing hypotheses from the two theories, and estimates a cross-population model for blacks and nonblacks using data from the Richmond Youth Project. Consistent with previous research, we find that broken homes have a larger impact on delinquency among blacks than nonblacks, but, unlike previous studies, our model explains this effect completely. In both populations, the effects of broken homes and attachment to parents and peers are mediated by the learning of definitions of delinquency, a finding that supports differential association over social control theory. (Author abstract)