The problem of dependability in end-user programming is an emerging area of interest. Pair collaboration in end-user software development may offer a way for end users to debug their programs more effectively. While pair programming studies-primarily of computer science students and professionals report positive outcomes in terms of overall program quality, little is known about specific activities that pairs engage in that lead to those outcomes, or of how the previous results may pertain to end-user programmers. In this study we analyze protocols of end-user pairs debugging spreadsheets. The results suggest that end-user pairs can achieve rich reasoning, effective planning, and systematic evaluation. Furthermore, end-user pairs provide specific types of mutual support that facilitate the accomplishment of their goals.