In a complex, dynamic multi-agent setting, coherent team actions are often jeopardized by agents' conflicting beliefs about different aspects of their environment, about resource availability, and about their own or teammates' capabilities and performance. Team members thus need to communicate and negotiate to restore team coherence. This paper focuses on the problem of negotiations in teamwork to resolve such conflicts. The basis of such negotiations is inter-agent argumentation (based on Toulmin's argumentation structure), where agents assert their beliefs to others, with supporting arguments. One key novelty in our work is that agents' argumentation exploits previous research on general, explicit teamwork models. Based on such teamwork models, it is possible categorize the conflicts that arise into different classes, and more importantly provide a generalized and reusable argumentation facility based on teamwork constraints. Our approach is implemented in a system called CONSA (COllaborative Negotiation System based on Argumentation).