This document summarizes factors that can lead to friendship and attraction between people. It discusses how proximity, physical attractiveness, similarity, liking those who like us, and rewarding interactions can foster the beginning of relationships. The document also examines theories of love, including the triangular theory of love which identifies three components - passion, intimacy, and commitment - that characterize different types of love and relationships. Close relationships are said to form through ongoing positive interactions that fulfill our deep-seated need to belong.