Borderline personality disorder (BPD) has been described as clinically heterogeneous, with numerous subtypes of the disorder posited. The present study investigated this potential heterogeneity by conducting both confirmatory factor analysis and latent class analysis of consensus ratings of Diagnostic and Statistical Manual of Mental Disorders (DSM) Revised Third Edition BPD criteria in a mixed clinical and nonclinical sample (n = 411). Confirmatory factor analysis results suggested that a single factor fit the data most parsimoniously. Latent class analysis results supported 2 latent classes: those with a high likelihood of BPD symptoms (n = 171) and those with a low likelihood (n = 240). The borderline latent class was more inclusive than diagnoses made based on DSM-III-R thresholds and improved prediction of symptom severity and interpersonal dysfunction, suggesting the clinical importance of 3 or more BPD criteria. Future research on subtypes of BPD may benefit by focusing on variables that supplement the DSM criteria.