With conventional oil production in decline, the global oil industry is investing heavily in dirtier and riskier forms of unconventional oil such as heavy crude, tar sands, and oil shale. These investments pose a challenge to the climate, the environment, and local communities. This paper is a document that describes the drivers behind marginal oil investments and gives an overview of existing and potential projects across the globe. It contains important analysis that should be public knowledge and will productively feed the ongoing debate, from Cancun to Durban to Rio and beyond.