Governance is recognized as a means to promote sustainable outcomes by democratizing the policy process and potentially harmonizing competing policy interests. This is particularly critical for sustainable tourism policy with its multiple sectors and multiple stakeholders at multiple scales. Yet little is known about the kinds of governance processes and instruments that are able to effectively harmonize competing power interests to better balance economic, ecological, and social concerns. This study analyzes the case of Bhutan and its Gross National Happiness (GNH) strategy as it is applied to sustainable tourism policy. Based on semi-structured interviews and focus groups with 57 state and non-state governance actors, it explores whether Bhutan’s unique GNH governance framework successfully harmonizes competing interests in the pursuit of sustainable tourism policy. It argues that the implementation of Bhutanese tourism policy is characterized by diverse and unexpected applications of power by multiple policy stakeholders. These complex power dynamics are not shaped in a meaningful way by the GNH governance instruments. Nor are they rooted in a common understanding of GNH itself. While this situation should subvert sustainable tourism policy, a commitment among state and non-state governance actors to a common set of Buddhist-infused cultural values shapes and constrains policy actions in a manner that promotes sustainable tourism outcomes.