This research investigates whether first sexual intercourse during adolescence is associated with increased risk of first marriage dissolution and tests whether the results are consistent with causal or selection explanations. Drawing on a sample of 3,793 ever-married women from the 2002 National Survey of Family Growth, this study estimated event-history models of first-marriage dissolution. Results indicate that wanted sexual debut in later adolescence does not directly increase the risk of marital dissolution but is linked indirectly as a result of subsequent premarital sexual outcomes. Sexual debut that is not completely wanted or that occurs before age 16 is associated with increased risk of marital dissolution. The results suggest that the timing and context of adolescent sexual debut have important implications for marital stability.