Thousands of patients experience needless deaths and injuries as a result of errors while hospitalized for an unrelated problem. The lack of an established professional practice model (PPM) of nursing may be a contributing factor to patient care quality and safety breaches. The PPM of nursing was tested for its ability to affect nurse and patient outcomes. Using a retrospective/prospective research design, secondary data were collected from 2395 staff nurses on 15 inpatient-nursing units covering a 6-year timeframe. Data were analyzed using ANOVA and the Pearson correlation. Nurse and patient outcomes on 2 hospital campuses reached statistical significance. Positive correlations were seen between the initiation of a PPM and subsequent nurses' perception of quality of care, nurse interactions, decision making, autonomy, job enjoyment, and patient satisfaction. This study provides empirical evidence that a uniquely designed PPM in alignment with organizational context can indeed impact nurse and patient outcomes in a community health system.