This study investigated the role of intelligence, conservatism, personal values, and Openness in assortative mating. A sample of 32 couples was given questionnaires, which measured self-rated intelligence and partner-rated Openness, conservatism and values. Intraclass correlations (ICCs) were used to ascertain similarity within couples on the above variables. We found significant evidence of assortment for Openness, the facets of Artistic Interests, Intellect and Liberalism, conservatism and the personal values equality and leisure time. When conservatism was controlled for, Openness no longer produced a significant ICC. While there have been several studies in the area of mate choice utilising self-rating, there are few that compare partner-ratings and almost none that have attempted to look at partner-ratings alone. In particular this study serves to highlight the importance of conservatism in assortative mating.