This volume explains what qualitative research can do, when it is sensible to use or commission it, and (most crucially and controversially) how to tell good work from bad. The text is amply illustrated with examples of qualitative health care research studies. Further, the authors share a common ground with quantitative colleagues in rejecting the idea that qualitative research is a kind of creative art form rather than a tool of policy science. Thus their book presents a challenge to fashionable models of qualitative evaluation research, in arguing that qualitative researchers are not poets in residence, but vital partners in the great practical tasks of promoting health and caring for the sick.