The 1978 contract negotiations between the teachers and the school board of Philadelphia were important enough to draw in four identified types of third party: government officials (notably the mayor), neutral mediators, community interest groups (representing political, financial, parental, and general public interests), and the news media. The negotiations took place in a historical and political context that affected the amount of influence each third-party group could exert. Of particular significance in this instance was the active role taken by the mayor, who was highly conscious of the effect a strike could have on an upcoming city charter revision election that in its turn would determine whether he could run for a third term in office. This document analyzes the role played by the major third-party groups in terms of levels of activity, of access to the negotiations, and of influence. The historical and political context and relevant previous literature are discussed, and documentary sources as well as observations made by participants in after-the-fact interviews are used to generate data for the study. (Author/PGD)