Abstract
With the use of institutional theory, we study why organizations join a voluntary sustainable tourism association and how the organization–association dynamics change over time. We find a disconnection between the joining and monitoring motivations for the association and its members that leads to conflicting forces and confusion, resulting in goal misalignment and loss of monitoring data. Voluntary associations need to accommodate for organizations' need of social identity, the desire to learn from each other and the sense of belonging from membership (mimetic forces), with the desire to institutionalize the members to behave in increasingly standardized way (normative and eventually coercive forces).