%0 Journal Article %T Understanding professional stakeholders' active resistance to guideline implementation: The case of Canadian breast screening guidelines. %A Wang Z %A Bero L %A Grundy Q %J Soc Sci Med %V 269 %N 0 %D 01 2021 %M 33333377 %F 5.379 %R 10.1016/j.socscimed.2020.113586 %X Health guidelines aim to improve patient outcomes through the promotion of evidence-based practice. Yet, when a guideline's recommendations significantly differ from, or threaten the interests, values and preferred practices of end-users, organised and often very public resistance to guideline implementation may result. To explore this phenomenon, we theorise a case study consisting of the public discourse following the update to a primary care breast screening guideline in Canada in 2018. Informed by sociological perspectives on the professions and evidence-based medicine, this paper aims to explore: [1] why professional stakeholders form active resistances to the implementation of some clinical guidelines; and, [2] how professional values, perspectives, interests and/or experiences influence the stakeholders' stance. Current understandings have taken a reductive approach in conceptualising the exclusion of experts and their resistance as "conflict of interest." Rather, we suggest that resistance is the product of multiple areas of contention, stemming from tensions related to clinical and professional autonomy, medical jurisdiction, and the role of medical elites. We highlight considerations for future guideline development and implementation process changes to mitigate and resolve issues related to active resistance. These considerations include understanding resistance as a political strategy, increasing transparency of public input and coalition building as a part of the public response to active resistance.