In prior and ongoing SCOR studies, our research team has demonstrated gender and menstrual cycle/sex hormone influences on reactivity to laboratory-presented cues. Building from these laboratory findings, we propose taking two important next steps: (1) evaluating the experience of craving in the "real world" natural environment of female and male smokers, and (2) examining the impact of a safe and novel pharmacological intervention (oxytocin) on stress reactivity in female and male smokers.