Both the qualitative and quantitative paradigms have weaknesses which, to a certain extent, are compensated for by the strengths of the other. As indicated in this article, the strengths of quantitative methods are that they produce factual, reliable outcome data that are usually generalizable to some larger population. The strengths of qualitative methods are that they generate rich, detailed, valid process data that usually leave the study participants' perspectives in tact. This article discusses how qualitative and quantitative methods can be combined and it introduces the articles included in this issue.