Western countries abandoned the National Oil Company (NOC) model many years ago, but the rise of NOCs has shifted the balance of control over the world’s hydrocarbon resources. In the 1970s, NOCs controlled less than 10% of the world’s energy resources, but now they control more than 90% of reserves and 75% of production. This shift comes in concert with increased access to capital, expertise and technology, as NOCs build in-house capabilities that allow them to operate increasingly independently. NOCs have been increasing their ability to contract and manage operations through oilfield services companies. We see an evolution in roles and strategies for all oil and gas companies – including NOCs, international oil companies and independents. NOCs have seen their power and influence grow. Moreover, the demands on NOCs continue to evolve with changes in the global energy landscape – changes in demand, discovery of new sources, and national and geopolitical developments. As managers of their country's natural resources, NOCs have generally owned and managed their complete oil and gas supply chain from upstream to downstream activities, but now they are emerging as both potential partners and competitors on the international scene in search of upstream and downstream assets. While the rise of NOCs, accelerated by high oil prices, has seen the balance of control over hydrocarbon resources shift in their favor, we see an increasingly disparate range of political and economic roles, strategies, and performance. In this paper we discuss several important themes in terms of NOC strengths, weaknesses, opportunities and challenges.