This article provides an overview of the origins and use of relational data analysis (RDA). RDA is a multidimensional, multiphasic framework for unifying data analytic strategies across dimensions (quantitative/qualitative, causal/structural, observation/interpretation, etc.) and phases of analyses (conceptual, theoretical, and research analyses). RDA was developed within a relational metatheoretical methodological framework for overcoming the splits that have historically characterized methodological metatheory. The aim was to formulate a practical, ready-at-hand framework that the developmental scientist could use to unify the analysis of developmental change in real life "applied" settings as well as clinic and laboratory settings. (Contains 1 figure and 2 tables.)