本研究の目的は，二人によるソフトウェアデバッグの効率のよい方法を確立することである．本稿では，二人の作業者間の役割分担，および，情報文換の方法を分類し，実験を通してそれらの長所と短所を考察した．実験の結果，(）一人がデバッグに専念しもう一人がデバッグに役立つ情報を収集すること，(）プログラムのソースコードを共有し，ソースコード中にコメントを書く事で情報を伝達することがデバッグ時間の短縮に有効であることが分かった．Software debugging is often performed by more than one programmer working together. The goal of this research is to identify a model of how two person collaboratively perform a degugging task on a single program. Based on empirical studies we have conducted, we have identified patterns in task- and infromation-sharing, and applied them to analyze the ovserved collaborative debugging processes. The following two collabration patterns were found to be effective in degugging (1) one concentrated on a debugging task while the other collected potentially useful information about the program, and (2) the two shared one program source file in their editors instead of using duplicates and wrote comments iinto the file.