Background: Racial differences in patient trust have been observed, but it is unclear which physician communication behaviors are related to trust, and whether the relationship of communication and trust differs among black and white patients. OBJECTIVE:: We sought to determine whether there were associations between physician communication behaviors, visit process measures, and patient trust, particularly within racial groups. Methods: Study participants included 39 primary care physicians and 227 black and white hypertensive patients from community-based practices in Baltimore, MD. Physician informational and affective communication behaviors and visit process measures were coded from visit audiotapes using the Roter Interaction Analysis System. Patient trust was measured using items from the Trust in Physician Scale, and dichotomized (high/low). Logistic regression analysis using generalized estimating equations was used to assess the association of each physician communication behavior and visit process measure with patient trust, among the entire sample and then stratified by patient race. Results: Positive physician affect and longer visits were significantly associated with high patient trust in unadjusted analyses. After adjustment for covariates, positive physician affect remained a significant predictor of high patient trust in the overall sample (odds ratio 1.26; 95% confidence interval, 1.08, 1.48; P=0.004) and after stratification by race, among black patients (odds ratio 1.35; 95% confidence interval, 1.09, 1.67; P=0.006). Conclusions: Physician communication behaviors may have a varying effect on patient trust, depending on patient race. Communication skills training programs targeting emotion-handling and rapport-building behaviors are promising strategies to reduce disparities in health care and to enhance trust among ethnic minority patients. © 2012 by Lippincott Williams & Wilkins.