Within Session Rating Scale: A modification of the Within Session Rating Scale will be used to assess craving and mood during the procedures. This scale is anchored with the adjectival modifiers ("not at all and extremely"). There are four items assessing domains of craving (want/need/craving/ability to resist). For the market value item, the individual will be asked to name the dollar amount they would be willing to pay for cocaine if they could have it "now". Other items include anxiety and mood. These data will be collected prior to treatment, prior to MIST1, and immediately after each run of the MIST.