Long-term energy outlooks acid forecasting models are assuming an increasingly important role, given the concerns of greenhouse gas emissions, and the current need for analyzing options for meeting the Kyoto Target. The Focus of the paper is on oil and gas supply projections. We present useful insights into the complexities of projecting oil and gas supply, develop an analytical framework which explains the approach used by natural resources Canada (NRCan) in preparing oil and gas supply forecasts, solve the oil and gas supply model (OGSM) and give the projections of oil and natural gas supply and demand to the year 2020.