The paper introduces the concept of *distributed problem solving* (DPS), which involves the cooperative solution of problems by a decentralized and loosely coupled collection of problem solvers. The authors define DPS as a method that offers increased performance and provides a useful medium for exploring new problem-solving techniques. They present the *contract net* framework, which specifies communication and control in a distributed problem solver. Task distribution is viewed as an interactive process where nodes discuss and negotiate to execute tasks effectively. The paper emphasizes that protocols for DPS should help determine the content of transmitted information rather than just facilitating bit transmission. The authors demonstrate the use of the contract net framework in a simulated problem in area surveillance, showing how a network of nodes can form a dynamic map of traffic. They discuss the operation of a distributed sensing system and the mode of its self-organization. The paper also examines the transfer of control in DPS, comparing it with control mechanisms in earlier problem-solving systems. The results suggest that negotiation, as a form of contract negotiation, is a natural extension to these mechanisms. The paper concludes by abstracting features of the framework applicable to general problem solving, particularly the transfer of control, and discusses suitable applications, limitations, and open problems. The authors highlight the contributions of their work to distributed processing, distributed problem solving, and artificial intelligence.The paper introduces the concept of *distributed problem solving* (DPS), which involves the cooperative solution of problems by a decentralized and loosely coupled collection of problem solvers. The authors define DPS as a method that offers increased performance and provides a useful medium for exploring new problem-solving techniques. They present the *contract net* framework, which specifies communication and control in a distributed problem solver. Task distribution is viewed as an interactive process where nodes discuss and negotiate to execute tasks effectively. The paper emphasizes that protocols for DPS should help determine the content of transmitted information rather than just facilitating bit transmission. The authors demonstrate the use of the contract net framework in a simulated problem in area surveillance, showing how a network of nodes can form a dynamic map of traffic. They discuss the operation of a distributed sensing system and the mode of its self-organization. The paper also examines the transfer of control in DPS, comparing it with control mechanisms in earlier problem-solving systems. The results suggest that negotiation, as a form of contract negotiation, is a natural extension to these mechanisms. The paper concludes by abstracting features of the framework applicable to general problem solving, particularly the transfer of control, and discusses suitable applications, limitations, and open problems. The authors highlight the contributions of their work to distributed processing, distributed problem solving, and artificial intelligence.