This article discusses developments in the field of qualitative methodology since the publication of King, Keohane, and Verba's (KKV's)Designing Social Inquiry. Three areas of the new methodology are examined: (1) process tracing and causal-process observations; (2) methods using set theory and logic; and (3) strategies for combining qualitative and quantitative research. In each of these areas, the article argues, the new literature encompasses KKV's helpful insights while avoiding their most obvious missteps. Discussion focuses especially on contrasts between the kind of observations that are used in qualitative versus quantitative research, differences between regression-oriented approaches and those based on set theory and logic, and new approaches for bringing out complementarities between qualitative and quantitative research. The article concludes by discussing research frontiers in the field of qualitative methodology.