A wealth of research from the past two decades shows that addictive behaviors are characterized by attentional biases for substance-related stimuli. We review the relevant evidence and present an integration of existing theoretical models to explain the development, causes, and consequences of addiction-related attentional biases. We suggest that through classical conditioning, substance-related stimuli elicit the expectancy of substance availability, and this expectancy causes both attentional bias for substance-related stimuli and subjective craving. Furthermore, attentional bias and craving have a mutual excitatory relationship such that increases in one lead to increases in the other, a process that is likely to result in substance self-administration. Cognitive avoidance strategies, impulsivity, and impaired inhibitory control appear to influence the strength of attentional biases and subjective craving. However, some measures of attentional bias, particularly the addiction Stroop, might reflect multiple underlying processes, so results need to be interpreted cautiously. We make several predictions that require testing in future research, and we discuss implications for the treatment of addictive behaviors.