This study uses questionnaire data from 301 terminated romantic relationships to investigate hypotheses concerning the conditions under which a quality that is initially appealing in a partner is later disliked (i.e., a “fatal attraction”). Individuals are expected to be prone to fatal attractions when they are attracted to a quality in a romantic partner that is “different” in any of three ways: (1) different from the individual's own qualities (i.e., dissimilar); (2) different from average (i.e., extreme, or unique); or (3) different from normative expectations (i.e., gender atypical). Such attractions are less likely, however, when individuals are drawn to similarity in another. Findings from a logistic regression analysis provide support for four of the five hypotheses. Fatal attractions are significantly more likely when an individual is drawn to partner characteristics seen either as “dissimilar” from her or his own, as “unique,” or as “extreme” in nature. When these characteristics are viewed as “similar,” disenchantment is less likely. Fatal attractions are neither more, nor less, probable, however, when partner qualities contradict gender stereotypes. A qualitative analysis of open-ended questionnaire responses provides further support for these attraction patterns. The findings have implications for diverse theories, including those of mate selection and dialectics.