Objectives. The authors investigate whether the argument from life-course criminology that marriage leads to reduction in crime or whether the mechanisms leading to lower crime rates might take effect in a period of courtship before the transition to marriage. Method. Using data from population-wide, longitudinal Norwegian administrative registers, the authors estimate within-individual offending propensities before and after marriage for all men marrying in Norway 1997–2001. This approach allows for studying how offending develops over a decade around the time of marriage, for those men who actually marry. Results. The propensity to offend declines sharply prior to marriage. After marriage, there is a small increase in offending. This holds both for all offenses and when the analysis is restricted to felony offenses. Conclusions. The analysis provides no evidence for an effect of marriage on offending. Rather, the results suggest that the lower offending rates of marrieds develop over the years prior to marriage rather than as a consequence of the marriage.