This paper examines two questions: (1) in a high oil price (and operating cost) environment what are typical breakeven prices for CO2? and, (2) are these prices sufficient to incentivize development of large-scale CCS projects? To address these questions we have developed an engineering-economic model for geological storage of CO2 through EOR. In this paper we briefly describe the performance and cost models for CO2-flood EOR, and use them to estimate the breakeven price for CO2 as a function of significant variables. In particular, the relationship between breakeven CO2 price and oil price is developed for four illustrative cases, all of which are, or were, operating EOR projects in North America. The sensitivity of the breakeven CO2 price to variability and uncertainty in reservoir characteristics and other model input parameters is also examined in detail for one of the cases.