The purposes of this project are to develop behavioral coding measures of humility and to provide evidence of the social benefits of humility. The validity of self-reports of humility has been questioned, as claiming to be humble on such measures seems akin to bragging. To address this problem, our model of relational humility aligns with the study of personality judgments, in which the gold-standard of measurement involves triangulation of self-report, other-report, and observation of behavior. However, there are currently no observational measures of humility. The activities of this project include leveraging and extending four already funded studies (one pilot study on individuals and three longitudinal studies on couples) to develop and offer evidence for the reliability and validity for three observational measures of humility. To increase accessibility for both scientists and practitioners, we will compare different strategies to examine the optimal balance between cost-effectiveness and criterion-related validity. We also examine evidence of incremental predictive validity relative to survey measures of humility. For criterion-variables, we focus on three important hypotheses that should catalyze research on humility: We theorize that humility (a) strengthens social bonds (social bond hypothesis), (b) buffers the negative impact of competitive traits on relationships (social oil hypothesis), and (c) is associated with better reactivity and recovery from stress (health-promotion hypothesis). This project will produce one key measurement paper and at least 8 other empirical journal articles (2 per study), as well as 4 colloquia or conference presentations. To disseminate findings to a popular audience, we will build a website designed to consolidate research on humility. This will be the first attempt to study humility through observational methods and has the potential to catalyze growth in the study of humility and related fields.