Over the past decades, professional medical authority has been transformed due to internal and external pressures, including weakened institutional support and patient-centered care. Today’s patients are more likely to resist treatment recommendations. We examine how patient resistance to treatment recommendations indexes the strength of contemporary professional authority. Using conversation analytic methods, we analyze 39 video recordings of patient-clinician encounters involving pediatric epilepsy patients in which parents resist recommended treatments. We identify three distinct grounds for parental resistance to treatments: preference-, fear-, and experience-based resistance. Clinicians meet these grounds with three corresponding persuasion strategies ranging from pressuring, to coaxing, to accommodating. Rather than giving parents what they want, physicians preserve their professional authority, adjusting responses based on whether the resistance threatens their prerogative to prescribe. While physicians are able to convert most resistance into acceptance, resistance has the potential to change the treatment recommendation and may lead to changed communication styles.