The article discusses the complexity of economic, ecological, and social systems, emphasizing the need for an integrative theory to understand and manage sustainability. It introduces the concept of panarchy, which describes systems that consist of hierarchies and adaptive cycles. These cycles allow for innovation and experimentation while maintaining stability. The panarchy model suggests that each level of a system operates at its own pace, protected by larger, slower levels but influenced by smaller, faster cycles of innovation. The article highlights the importance of sustainability, which is defined as the capacity to create, test, and maintain adaptive capability. Sustainable development combines this adaptive capability with the process of creating and maintaining opportunity. The text argues that sustainability is not an oxymoron but a logical partnership between adaptability and opportunity. The article also discusses two views of complexity. One view sees complexity as the result of many interacting elements that are not understood. The other view suggests that complexity arises from a small number of controlling processes that self-organize. These processes create and maintain the system's structure. The article emphasizes the need for a theoretical framework that is both simple and complex enough to understand and communicate. It argues that such a framework should be dynamic and prescriptive, not static and descriptive. It should embrace uncertainty and unpredictability, as these are inevitable in systems of people and nature. The article concludes by stating that the purpose of the paper is to summarize a theoretical framework and process for understanding complex systems. This framework has been developed and expanded into a book-length thesis, which provides a means of assessing information about internal factors and external influences that determine systemic sustainability. The framework must be simple enough for understanding and communication, dynamic and prescriptive, and embrace uncertainty and unpredictability.The article discusses the complexity of economic, ecological, and social systems, emphasizing the need for an integrative theory to understand and manage sustainability. It introduces the concept of panarchy, which describes systems that consist of hierarchies and adaptive cycles. These cycles allow for innovation and experimentation while maintaining stability. The panarchy model suggests that each level of a system operates at its own pace, protected by larger, slower levels but influenced by smaller, faster cycles of innovation. The article highlights the importance of sustainability, which is defined as the capacity to create, test, and maintain adaptive capability. Sustainable development combines this adaptive capability with the process of creating and maintaining opportunity. The text argues that sustainability is not an oxymoron but a logical partnership between adaptability and opportunity. The article also discusses two views of complexity. One view sees complexity as the result of many interacting elements that are not understood. The other view suggests that complexity arises from a small number of controlling processes that self-organize. These processes create and maintain the system's structure. The article emphasizes the need for a theoretical framework that is both simple and complex enough to understand and communicate. It argues that such a framework should be dynamic and prescriptive, not static and descriptive. It should embrace uncertainty and unpredictability, as these are inevitable in systems of people and nature. The article concludes by stating that the purpose of the paper is to summarize a theoretical framework and process for understanding complex systems. This framework has been developed and expanded into a book-length thesis, which provides a means of assessing information about internal factors and external influences that determine systemic sustainability. The framework must be simple enough for understanding and communication, dynamic and prescriptive, and embrace uncertainty and unpredictability.