The concept of sustainability has taken centre stage in Arctic politics. However, there is little agreement on what ‘sustainable’ means. For different actors (NGOs, indigenous people, states, companies) the concept implies different sets of opportunities and precautions. The paper presents a first step in a collective research project that aims to map and analyse the role of sustainability in various political and economic strategies in the Arctic. Traditionally sustainability invokes technical-rational authority to inform development policies. But sustainability has become a fundamental concept that orders the relationship between development (change), society (identity), the environment (nature) and security (state). We, first, present an attempt to capture sustainability as a political theoretical concept. Second, we discuss how sustainability changes its meaning when meeting the Arctic (from concerning the global ecosphere to a more limited environment), and how sustainability is conceptually transforming to allow rather than limit development in a fragile Arctic environment.