This study examines the effects of a Catholic background on age at first marriage, the odds of never marrying, and the odds of ever divorcing. Estimates using Catholic upbringing are compared with estimates using Catholic at the time of the survey. A case is made that if the latter measure of Catholicism is used, serious selection bias problems occur in some cases because this measure excludes defectors and includes converts. Further, it is shown that a Catholic upbringing generally has no effect on men’s age at first marriage and has a positive effect on the age when women marry. It is also shown that older Baptist men are substantially more likely than Catholic men to experience a divorce. Older Catholic women are somewhat less likely to experience a divorce than non-Baptist Protestant women. There is no Catholic effect on the odds that younger men and women will divorce.