OBJECTIVES: To examine family physicians' attitudes and willingness to prescribe long-acting opioids to patients with moderate to severe chronic nonmalignant pain (CNMP). METHODS: The Theory of Planned Behavior (TPB) was used to examine the underlying constructs (i.e., attitude, social influences, and perceived control) believed to influence physicians' willingness to prescribe long-acting opioids for CNMP. Three focus groups were conducted and a web-based survey was developed, pre-tested, and e-mailed to 2750 Texas family physicians. A total of 64 Likert-type questions were used to assess the predictors of physicians' willingness to prescribe, and 10 of these items measured physicians' attitudes (summed range = -90 to +90). RESULTS: A total of 267 family physicians completed the questionnaire. The TPB model accounted for 39% (F3222= 47.4, p<0.001) of the variance in explaining physicians' willingness to prescribe. Most physicians (N=179, 66%) indicated that they were willing to prescribe long-acting opioids to their CNMP patients. Physicians unwilling to prescribe long-acting opioids for CNMP had an overall unfavorable attitude (Mean= -7.87, SD= 17.43) compared to willing physicians (Mean= +9.56, SD= 17.42). Unwilling physicians held stronger beliefs that prescribing opioids would lead to patient abuse, addiction and regulatory scrutiny compared to willing physicians. A significant positive relationship was found between previous prescribing of long-acting opioids and attitude (R= 0.46, p<0.01). Respondents who prescribed long-acting opioids more often were less likely to believe that it would lead to abusive and addictive behaviors, while those who prescribed less often were more likely to believe that it would lead to regulatory scrutiny. CONCLUSION: The TPB model was a significant predictor of physicians' willingness to prescribe long-acting opioids. Two-thirds of the family physicians were willing to prescribe long-acting opioids for moderate to severe CNMP. However, attitudinal barriers exist among those physicians unwilling to prescribe. Educational interventions should focus on these barriers.