The importance of considering research design in a wider context.

This paper reflects on the importance of considering research design in relation to the question at hand, and argues that the "best" method maximises both rigor and appropriateness. It comments on some of the papers published in this supplement, and emphasises that different audiences will have different needs in terms of the level of evidence required. Suggestions are made how some of the problems associated with randomized trials of Complementary Therapies can be overcome.