Despite a traditional advocacy role, tax professionals face growing pressure to help manage the tax fraud problem. However, the authoritative tax literature lacks explicit guidance in the area, motivating questions about the extent tax professionals perceive fraud detection responsibility. This study evaluates 236 tax professionals' perceived responsibility for tax fraud detection, and the extent that tax engagement type (planning versus compliance) and audit client status (audit client versus not an audit client) affect responsibility. We also use the triangle model of responsibility to test the extent that task clarity, professional obligation, and personal control mediate the effects of engagement type and audit client status on detection responsibility. The results indicate moderate and varied perceived detection responsibility among the participants. We also find that reported detection responsibility varies across tax engagement type and audit client status. As expected, tax professionals report higher detection responsibility in a tax compliance engagement and when the tax client is also an audit client. Subsequent path analysis results show that the triangle model components are positively related to detection responsibility, and that professional obligation and personal control mediate the effects of engagement type and audit client status on detection responsibility.