This paper presents a report and analysis of simulated negotiations in a multiparty institutional context, specifically a Canadian Aboriginal-Crown context. The purpose is to offer a conceptual model of skills and processes of successful negotiations under such circumstances. The Aboriginal-Crown subject of the simulation has particular relevance in light of Canada's Supreme Court declaration in Delgamuukw v. British Columbia, [1997] 3. S.C.R. 1010 at para. 186 (quoting itself from Sparrow v. The Queen, [1990] 1 S.C.R. 1075) that Section 35(1) of the Constitution Act, 1982 "provides a solid basis upon which subsequent negotiations can take place." The vehicle of the analysis is participant reflections, which offer a 360-degree view of the simulation, selected, classified, and combined into a conceptual model by the instructor. Multiparty institutional conflicts are large-scale social and organizational conflicts involving multiple groups that have historical, social, cultural, and economic significance, potential legal claims and remedies, and ongoing relationships. Formal negotiations in a multiparty institutional context consider possible changes to some aspect of current institutional arrangements, which are the legal and policy rules governing group relationships. Multiparty institutional negotiations are high stakes because the goal is institutional reform that will affect large numbers of people over the long term. Neither the outcome of negotiating nor of any particular reform is predictable. Leaders find such uncertainty a heavy challenge, and often participate only when facing even greater risks through violence, institutional breakdown, or external threats.