This paper examines the phenomenon of "green alliances" between businesses and their suppliers, competitors and other stakeholders. The concept of a "green alliance" is explored as a form of green marketing strategy and different types of alliance are set out. Drawing on stakeholder theory and the networks model of industrial markets, critical environmental interdependencies between organizations are identified and examined. An exploratory case study covering a range of such interdependencies is reported, with issues of alliance motives, and of inter- and intra-organizational relationships and cultures examined in considerable detail. Issues identified as critical to the alliance process include the congruity of bonds between various alliance actors, resources and activities, and the cultural mediation between diverse stakeholder factions. The implications of these findings for environmental change and for green marketing management are discussed.