This study sought to examine the self-esteem of individuals involved in a consensually non-monogamous relationship, the swinging lifestyle. Utilizing the Rosenberg Self-Esteem Scale, the self-esteem of swingers was quantified and compared to a general sample. The results reveal that swingers have higher self-esteem. However, gender differences emerged in post hoc analyses whereby men who engage in swinging have higher self-esteem, but women who engage in swinging have self-esteem comparable to others. Results are discussed in terms of evolutionary and clinical importance. Limitations and future directions are also discussed.