This dissertation concerns the ways engineers and safety specialists acting as part-time volunteers cooperate in the setting of voluntary industrywide product safety standards in the farm equipment industry. These cooperative efforts are based, I contend, on collective investment criteria shared by both companies and individual participants. companies expect long-term benefits stemming not only from their early access to information about the proposed changes in product design, but also from the extent they can influence the outcome in ways that reduce their costs and accommodate their product design and manufacture requirements. Individual participants expect to benefit professionally from the knowledge exchanges taking place in the deliberations. I illustrate my argument through a case study in the development of a family of safety standards for agricultural tractors. The study shows that, in setting these standards, participants sought and achieved ways of making their proposed changes in product design more compatible with a changing legal order. The study also shows, however, that collective action may bring some unintended consequences. For instance, given the stiff demands of this order, participant companies' collective efforts to build such compatibility may and did ultimately compromise the voluntary character of both their participation in the deliberations and the implementation of the proposed changes in product design