The current study assessed if childhood sexual abuse (CSA) can be meaningfully classified into classes, based on the assumption that abuse by a close family member differs in important ways from other abuse, and whether abuse classes were differentially associated with couple relationship problems. The childhood experiences and adult relationships of 1,335 Australian women (18-41 years) were assessed. Latent class analysis identified three classes of CSA: that perpetrated by a family member, friend, or stranger, which differed markedly on most aspects of the abuse. Family abuse was associated with the highest risk for adult relationship problems, with other classes of CSA having a significant but weaker association with adult relationship problems. CSA is heterogeneous with respect the longterm consequences for adult relationship functioning.