: Physiotherapists, as with all other healthcare professionals, report attitudes toward patients with obesity and beliefs about obesity that contribute to weight bias and stigma. : Determine if physiotherapists' attitudes and/or beliefs changed after attending an educational seminar that included content about the challenges faced by patients with obesity undergoing joint replacement and strategies on how to work effectively and sensitively with this population. : Physiotherapists completed a survey before and after attending a one day seminar to evaluate attitudes (The Attitude Towards Obese Persons, ATOP) and beliefs (Beliefs About Obese Persons, BAOP) towards obesity. To provide a reference, the seminar group's attitudes and beliefs were compared to a provincial cohort of 383 physiotherapists who completed the online version of the survey. : The pre-seminar mean ATOP score (71.3 ± 19.3) was similar to the online mean score (72.6 ± 15.3) ( = .66). The post-seminar ATOP score decreased (63.6 ± 15.9) ( = .02) indicating greater negative attitudes. The mean difference of the seminar BAOP showed a modest increase (mean difference 4.6, = .001) indicating that participants believed obesity was less in control of the individual. : Seminar information presented by respected and trusted leaders did not challenge participants' implicit attitudes and beliefs towards obesity. Further evaluation of theory-driven approaches specifically targeting physiotherapists is needed to address stigmatization within the profession.