Canadian oil sands production is set to double in the next decade, cementing its place as a leading source of marginal oil. Its growing market share of the 53% of global supply produced by non-Organisation of Petroleum Exporting Countries (Opec) is likely to give it an increasingly pivotal role in future global oil markets. However, pricing bottlenecks, concerns about environmental regulatory approval and the need for greater market diversification outside the US will constrain any effect on