The impact of new onshore North America 2018–19 volumes continues to have profound impacts on global supply into the near to medium term. Not least because of the volatility challenging anew operators’ investment plans and budgets. Fast approaching in parallel, the investment shortfall in longer-cycle barrels over 2015–19 materializes in the next few years, because of delays in a significant number of project FIDs and undrilled wells, even as redesign, automation, and optimization efforts accelerate. The longer-term stability and durability of the global supply system depends on the efficiency with which barrels are sourced from an increasingly global and diverse resource base. What are the different components of crude supply over the coming years and what are the critical sensitivities?