Corticotropin-releasing factor (CRF)-mediated mechanisms in the bed nucleus of the stria terminalis (BNST) have a pivotal role in stressinduced anxiety and hyperalgesia. Although CRF is known to activate two receptor subtypes, CRF 1 and CRF 2 , attempts to delineate the specific role of each subtype in modulating anxiety and nociception have been inconsistent. Here we test the hypothesis that CRF 1 and CRF 2 receptor activation in the anteriolateral BNST (BNST AL ) facilitates divergent mechanisms modulating comorbid anxiety and hyperalgesia. Microinfusions of the specific antagonists CP376395 and Astressin 2 B into the BNST AL were used to investigate CRF 1 and CRF 2 receptor functions, respectively. We found that CRF 1 and CRF 2 receptors in the BNST AL had opposing effects on exploratory behavior in the elevated plus-maze, somatic mechanical threshold, and the autonomic and endocrine response to stress. However, CRF 1 or CRF 2 receptor antagonism in the BNST AL revealed complementary roles in facilitating the acoustic startle and visceromotor reflexes. Our results suggest that the net effect of CRF 1 and CRF 2 receptor activation in the BNST AL is pathway-dependent and provides important insight into the CRF receptor-associated circuitry that likely underpins stress-induced pathologies.