Collaborative, team-based research is now the most significant mode of activity in the global scientific community. Anecdotal and statistical evidence shows moreover that collaboration in scientific research is increasingly global in nature. That is, the groups of researchers who are involved in scientific progress often span one or more nations in origin, location and/or sponsorship. Another significant trend in recent cases of scientific collaboration is the increase in cross-sectoral cooperation, where researchers in a group are employed by government, private industry, and/or academic and other non-profit institutions. In this paper, we review the scale, scope and intensity of cross-national, cross-sectoral research collaboration through the analysis of historical data on co-authorship of scientific publications. The first part of the paper reviews existing literature on the analysis of co-authorship data, and discusses the limitations of this form of analysis and typical strategies to mitigate those limitations. The second part of the paper describes a preliminary study of cross-national, cross-sectoral scientific collaborations covering the years 1988 through 1997, where we examined the scale (volume of co-authored papers), intensity (co-authored papers versus other kinds of co-authorship), and scope (patterns in co-authorship) for cross-national, cross-sectoral collaborations. The conclusion of the paper discusses significant trends and patterns derived from this study, and their implications for further research into these types of collaborations.