His work focuses on close relationships, and he uses diverse methodologies including neuroimaging, gene mapping, and advanced cognitive techniques to study attachment, sex, and caregiving. He has published extensively on the topics of interpersonal relationships and relationship neuroscience in leading academic journals, and has two books focusing on these topics; Adult Attachment: A Concise Introduction to Theory and Research, and Relationship Science: Integrating Evolutionary, Neuroscience, and Sociocultural Approaches.