The movement toward integration of qualitative and quantitative research methods within the same study has been most evident in social policy research. Four major approaches to integrating can be identified in recent studies. The sequential, the parallel, and the fused models have been rather widely used. The interactive model, developed during the course of the study of the Research and Development Utilization (RDU) program is relatively new. The first three models are presented briefly, and the interactive model is discussed in greater depth, with attention given to how it evolved during the course of the RDU study. The use of "consolidated coding" to merge data collected by survey with that collected through semi-structured site visits is discussed. Some of the issues and problems associated with the research methods are presented. (Author/MLF)