This document discusses the need for association leaders to think about new business models to ensure relevance and thrive in a changing society. It notes that disruption is everywhere and the future is uncertain. Relevance alone is not enough; associations must connect opportunities to their responsibilities. The document introduces business model thinking and canvases as tools to analyze an association's current model and develop new concepts. It provides principles for 21st century association business models, emphasizing purpose, intimacy, networks, collaboration and openness. The goal is to help associations thrive over the coming decades.