The way in which adolescents cope with stressors in their lives has been established as an important correlate of adjustment. While most theoretical models of coping entail unfolding transactions between coping strategies and emotional arousal, the majority of coping measures tap only trait-level coping styles, ignoring both temporal and affective components of the coping process. The current study fills this gap by establishing the psychometric properties of a newly developed measure, the Adolescent Coping Process Interview (ACPI), that is more in line with transactional and developmental models of coping. Results indicate that the ACPI displays good psychometric properties, captures significant intra-individual variability in coping over the process, and points to emotional arousal as informing several coping-adjustment relationships. Moreover, the ACPI and similar approaches may help promote the development of more adaptive patterns of coping in adolescents by helping to identify specific points within the coping process at which to intervene