Although prior research (Montoya, Horton, & Kirchner, 2008) has indicated that perceived similarity is more important than actual similarity as a predictor of satisfaction and attraction, there is a lack of research on factors associated with couples' perceptions of similarity in their relationship. In the present study, a sample of couples (both partners) provided ratings of the degree to which they perceived similarity in six areas (background characteristics, attitudes and beliefs, leisure pursuits and interests, communication style, personality, and physical attributes) for two stages in their relationship: currently and at the initiation stage (viewed retrospectively). The couples perceived greater similarity for the current stage of their relationship than for the beginning stage of their relationship. Factors found to be associated with perceived similarity included positive social network reactions, overlap in social networks (predictor of current perceived similarity only), perceived compatibility, and satisfaction and commitment (examined only for current perceived similarity). Of the various types of perceived similarity considered in this study, similarity in attitudes and beliefs was most consistently associated with the various predictor variables. Implications of these results for enhancing couple relationships are discussed.Keywords: perceived similarity, similarity-attraction hypothesis, attraction-similarity model, satisfaction, social networks Interpersona, 2013, Vol. 7(2), 180-195, doi:10.5964/ijpr.v7i2.126 Received This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Decades of research in the areas of interpersonal attraction and close relationships have established the important role of similarity, both in the development of relationships and in established relationships (Byrne, 1971;Newcomb, 1961). In addition, similarity has been found to be important in many different cultures (e.g., Byrne et al., 1971).The similarity-attraction hypothesis refers to the principles that people become attracted to those who are similar to them, are more satisfied in relationships with similar others, and dissolve relationships when there are dissimilarities (Morry, 2009). People can be similar to a partner on a number of dimensions, including attitudes and beliefs, personality, leisure interests, communication styles, and sociocultural background factors (Baxter & West, 2003).Various theoretical explanations have been provided for why similarity leads to attraction and satisfaction, including that similarity (especially in attitudes and beliefs) is consensually validating and reinforcing (Byrne, 1971;Clore & Byrne, 1974), similarity leads to uncertainty reduction and predictability (Berger & Calabrese, 1975), and similarity can lead to enjoyable and fun interactions (Berscheid & ...