Her research focuses on the development and maintenance of close relationships. Cobb has investigated how relationship processes such as conflict, aggression, and support predict relationship trajectories, and how personal and context factors (e.g., attachment security, depression, stress) moderate the association between relationship processes and changes in relationship satisfaction over time. She has also investigated how participation in naturally occurring relationship education programs in the community relates to changes in newlywed marriage, and whether participation in relationship skill building programs prevent relationship distress.