Erina Lee discusses the importance of similarity between partners in terms of long-term relationship satisfaction. She discusses some compatibility dimensions that have been considered by eHarmony, as well as future directions for research. Erina Lee of eHarmony Labs discusses the importance of similarity between partners in the context of different kinds of online relationship. She explains how similarity is indelibly intertwined with long-term relationship satisfaction, and reveals the surprisingly high levels of cultural variation in the way that similarity can be constructed. She goes on to discuss some of the many dimensions of compatibility that have been considered by eHarmony, before giving her thoughts on future directions for research on matchmaking to the OII's own Bernie Hogan.