Though few students of psychology and related social or behavioural sciences go on to be laboratory-based experimentalists, traditional courses concentrate largely on the design and analysis of laboratory experiments. Many graduates do however go on to jobs where they are called upon to carry out some form of enquiry task outside the laboratory - often in complex, poorly-controlled situations. Practitioners and professionals working with people (eg. in education, health and the social services as well as in industry) are increasingly being required to be involved in similar studies. This new text gives advice and support in the carrying out of such real world research. The emphasis is on achieving rigour and trustworthiness in the enquiry through systematic procedures appropriate to the task. Particular features include an advocacy of multi-method case study as a serious research strategy alongside field experimentation and the survey; and an even-handed coverage of qualitative and quantitative approaches. Many real world studies are evaluations and their distinctive features are stressed. A final section covers issues in "making an impact", including different approaches to reporting, the place of enquiry and promoting change, and the relative roles of practitioners and researchers.