The Norwegian petroleum resource management model is based on a licensing regime set out in the Norwegian Petroleum Act, with further details provided in the Petroleum Regulations. The Act governs the lifecycle of petroleum operations from cradle to grave through a step-by-step licensing approach. The main considerations and principles behind the Petroleum Act are discussed in earlier chapters of this book. In this chapter, we will provide an overview of the content and structure of the licensing system, following a stepwise approach from the opening of the petroleum areas to the decommissioning of installations. Upstream oil and gas activities have different impacts on their surrounding environment at different stages of their exploration, production and transformation into sellable assets. In this chapter, we will therefore also examine the manner in which offshore petroleum activities are regulated with respect to their interaction with the surrounding environment.