Purpose: To report the baseline characteristics of a US multi-ethnic, multi-regional, multi-institution cohort of patients with systemic lupus erythematosus (SLE) and how it was constituted. Methods: Patients with SLE per American College of Rheumatology (ACR) classification criteria, 16 years of age and older, with disease of 10 years or less, of Hispanic (H), African American (AA) or Caucasian (C) ethnicity and living in the geographic catchment areas of the participating institutions (the University of Alabama at Birmingham (UAB), Johns Hopkins University (JHU), The University of Texas-Houston Health Science Center (UTH) were eligible to enter the combined cohort (PROFILE, herein). Data from the individual SLE cohorts were pooled and the PROFILE cohort characteristics examined using descriptive statistics. Variables predictive of renal damage were then examined by logistic regression. Results: The PROFILE cohort constituted by 568 patients (H = 78, AA = 216, C = 260 (13 other ethnicities)) is predominantly female. Non-C had a greater number of ACR criteria, and of renal involvement. Among the two non-C groups, a higher proportion of H patients have developed overall renal damage, as well as decreased glomerular filtration rate. Other than Hispanic ethnicity (odds ratio, OR=6.27, confidence limits, CL=1.96-220.01), sustained hypertension (OR= 14.16, CL = 4.52-4.43) was a significant predictor of renal damage, whereas belonging to the JHU cohort was protective (OR = 0.18, CL = 0.05-0.63). Conclusions: We have constituted a large US multi-ethnic SLE cohort. Renal involvement was found to be more frequent among the non-C; within them, the H patients seem to be at higher risk for the occurrence of renal damage. © 2002 Arnold.