System of systems is a collection of task-oriented or dedicated systems that pool their resources and capabilities together to create a new, more complex system which offers more functionality and performance than simply the sum of the constituent systems. Currently, systems of systems is a critical research discipline for which frames of reference, thought processes, quantitative analysis, tools, and design methods are incomplete. The methodology for defining, abstracting, modeling, and analyzing system of systems problems is typically referred to as system of systems engineering. Overview Commonly proposed descriptions—not necessarily definitions—of systems of systems, are outlined below in order of their appearance in the literature: Linking systems into joint system of systems allows for the interoperability and synergism of Command, Control, Computers, Communications and Information (C4I) and Intelligence, Surveillance and Reconnaissance (ISR) Systems: description in the field of information superiority in modern military. System of systems are large-scale concurrent and distributed systems the components of which are complex systems themselves: description in the field of communicating structures and information systems in private enterprise. System of systems education involves the integration of systems into system of systems that ultimately contribute to evolution of the social infrastructure: description in the field of education of engineers on the importance of systems and their integration. System of systems integration is a method to pursue development, integration, interoperability and optimization of systems to enhance performance in future battlefield scenarios: description in the field of information intensive systems integration in the military. Modern systems that comprise system of systems problems are not monolithic, rather they have five common characteristics: operational independence of the individual systems, managerial independence of the systems, geographical distribution, emergent behavior and evolutionary development: description in the field of evolutionary acquisition of complex adaptive systems in the military. Enterprise systems of systems engineering is focused on coupling traditional systems engineering activities with enterprise activities of strategic planning and investment analysis: description in the field of information intensive systems in private enterprise. System of systems problems are a collection of trans-domain networks of heterogeneous systems that are likely to exhibit operational and managerial independence, geographical distribution, and emergent and evolutionary behaviors that would not be apparent if the systems and their interactions are modeled separately: description in the field of National Transportation System, Integrated Military and Space Exploration. Taken together, all these descriptions suggest that a complete system of systems engineering framework is needed to