In April 1931, the American Dental Association’s Seal of Acceptance was introduced. It has been – and still is – widely praised as a symbol of safety, efficacy and credibility within dental therapeutics and an icon of professionalism for the American Dental Association. This paper traces the complex history of the introduction of the Seal of Acceptance and argues that the introduction revolved around personal zeal and struggles for the authority associated with the acceptance programme that had been launched in 1930 and was administered by the Council on Dental Therapeutics of the American Dental Association. The acceptance programme became a financial thorn in the side of the Board of Trustees of the American Dental Association and the editor of the Journal of the American Dental Association, as it reduced the revenue of the advertising section of the journal significantly. However, other parties in the conflict, including several members of the Council on Dental Therapeutics, interpreted the dwindling support from the Board of Trustees as undermining the professional ideals of the American Dental Association. The struggles to balance professionalism and finances came to open conflict in the journal as well as at a general meeting of the Chicago Dental Society’s Midwinter Clinic in 1931. Recently distributed power was withdrawn from the Council on Dental Therapeutics as the Board of Trustees sought to consolidate the journal’s financial situation. The American Dental Association’s Seal of Acceptance served as a tool in the redistribution of authority in this intra-professional conflict.