Mixed methods studies in social sciences are predominantly employed to explore broad, complex, and multifaceted issues and to evaluate policies and interventions. The integration of qualitative and quantitative methods in social sciences most often follows the Peircean pragmatic approach--abductive hypothesis formation followed by deductive and inductive testing/confirmation--with limited theorizing properties. This paper contributes to the field of mixed methods research in social sciences by explicating a two-way interaction process between mixed methods data and [social] theory in a pluralistic inferencing approach espoused by critical realism--retroductive theorizing. The paper further illustrates how through retroductive theorizing, critical realism offers a more epistemologically and ontologically grounded alternative for integrating qualitative and quantitative methods compared to pragmatism.