In this study, a new adult attachment scale, the Adult Exploration Support Schema (AESS), is presented. The AESS was based on the concept of the exploratory behavioral system, unlike most existing adult attachment measures that are grounded in the availability of attachment figures for the purpose of protection. Specific attention is given to the father version of the scale—Adult Exploration Support Schema–Father (AESS–F)—which is examined using a factor analytic approach to data from a racially and ethnically diverse sample of undergraduate students from a large urban American university in a Western state. Exploratory and confirmatory factor analyses supported the structural validity of AESS–F scores and the construct of secure adult-father attachment tied to the exploratory behavioral system. Associations between the AESS–F and existing adult attachment measures supported the convergent and divergent validity of AESS–F scores. Hierarchical linear regressions involving AESS–F and constructs of secure exploration (i.e., academic self-efficacy, work ethic, educational engagement, curiosity, and hope) provided support for the predictive validity of AESS–F scores, with AESS–F scores explaining more of the variance than an existing adult-father attachment measure rooted in secure base conceptualizations of attachment. These results suggest that an updated conceptualization based in the exploratory behavior system might be a useful addition to the literature on adult-father attachment.