Safety culture has many determinants, and studies in both inpatient and outpatient settings have shown that overall perception of safety culture varies between practice settings. This study used the AHRQ Medical Office Survey on Patient Safety Culture to evaluate perceived safety and quality of care in more than 300 primary care practices and found that smaller practices (those with fewer than 15 employees) generally had more positive perceptions of safety culture. The study did not find any relationship between safety culture and use of health information technology (IT), despite prior research showing that health IT implementation is associated with improved safety culture scores. The broader issue of patient safety in ambulatory care is discussed in a Patient Safety Primer.