Psychometric properties of the Hypersexual Behavior Inventory (HBI) are reported using treatment-seeking samples of hypersexual men. Study 1 details item reduction and exploratory factor analysis of the HBI. Study 2 provides results of a confirmatory factor analysis yielding a 3-factor model measuring Control, Consequences, and Coping associated with sexual thoughts, feelings, and behaviors. Concurrent and discriminant validity was established with measures of theoretically related and dissimilar constructs. The psychometric properties of the HBI suggest it reflects the proposed DSM-V classification criteria for hypersexual disorder and has both the clinical and research utility to advance a more comprehensive understanding of hypersexuality.