The Centers for Medicare & Medicaid Service's (CMS), national End-Stage Renal Disease (ESRD) Clinical Performance Measures (CPM) Project is a data collection initiative to identify opportunities for improvement of care to adult, Medicare maintenance dialysis beneficiaries. This analysis of 1999 CPM data characterizes the profile of hemodialysis vascular access in the United States and identifies determinants of vascular access type 2 yr after the translation of vascular access clinical practice guideline statements into national CPMs. CPM data were collected during October to December 1999 and stratified by the 18 regional ESRD networks. Univariate and multivariable analyses were conducted to examine associations of access type with demographic, laboratory, and geographic variables. Multivariable logistic regression analyses were performed to identify independent variables associated with access type. A total of 8154 hemodialysis patients were sampled; 17% (n = 1399) were incident. Twenty-eight percent were dialyzed through an autologous arteriovenous fistula (AVF), 49% through a prosthetic graft (AVG), and 23% through a percutaneous catheter. Independent predictors of having a catheter for hemodialysis were female gender, white race, incident to hemodialysis status, and lower hemoglobin and serum albumin. For patients with a fistula or AVG, female gender (odds ration [OR], 2.46 [2.18 to 2.78]) and black race (OR, 1.70 [1.50 to 1.93]) were the strongest predictors of dialysis through an AVG. Other predictors of dialysis through an AVG were older age, increased body mass index (BMI), diabetes mellitus as the cause of ESRD, and lower serum albumin. Even in adjusted analyses, there was significant geographic variability with respect to hemodialysis access type. Despite translation of practice guidelines for hemodialysis vascular access into national CPMs, there is substantial geographic variability and gender and racial disparity in angioaccess allocation in the United States. Quality improvement strategies to improve the prevalence of fistulae should focus on selected regions and include physician education about their practice patterns and potential biases.