This document describes a proposed research program for studying dispositional (personality) differences among individuals as predictors of changes in key indicators of healthy aging and disease risk over the middle years of life. The program aims to re-evaluate up to 875 men and women who previously participated in the Adult Health and Behavior (AHAB) project (conducted between 2001 and 2005) in the second wave of a proposed longitudinal study of aging. This work was submitted for funding consideration as part of a P01 (Program Project) grant to the National Institute on Aging (NIA) in May, 2015. The P01 application included two other projects, as well as Core facilities for centralized administration, program-wide data collection, and data management and biostatics. When the application appeared unlikely to meet the P01 pay line at NIA this year despite receiving a commendable priority score (19), we were invited to forward a plan for converting the highest scoring individual project into an R01 scope of funding. On offer was the possibility of moving this one project directly into the R01 funding pool without further scientific review. To do so required absorbing certain Core functions from the P01 application into the single project prospectus, which is accomplished in this document, along with a modified budget request.