Ample evidence implicates both environmental cues and negative affective states in maintaining drug use or triggering relapse. However, although 'craving' is believed to drive continued drug use, it is not well understood how cognitive processes influence craving and relapse, nor how they may differ between the sexes. Therefore, the goal of this study protocol is to provide insight into sex differences in the cognitive aspects of drug craving and to assess the impact of stress on attentional bias for drug-related cues as well as on the availability of cognitive resources.