Future military operation environments are expected to be characterised by dependencies, great uncertainty and rapid change. A concept focusing on C2 in military operations is being developed to enable C2 capability within the Armed Forces in these environments. The concept includes one founding principle and eight guiding principles. The founding principle is: C2 concept 2045 (Ledk45) aims to create effective, agile and resilient C2 that provides prerequisites for action individually and in collaboration with others. The guiding principles are: (1) C2 across force and domain boundaries, (2) Adaptation of C2 forms, (3) Adaptation of C2 capability, (4) Adaptation of C2 organisation, (5) Adaptation of C2 mobility, (6) Adaptation of the geographical distribution of command posts, (7) Interoperability, and (8) Continuous development. The report further describes how Ledk45 can be instantiated, based on possible use of technology as well as a different types of command posts. Finally, the report describes the foundation for the development of Ledk45, including C2 needs, doctrine, method, organisation, personnel and technology. The development of Ledk45 is mainly based on identified C2 needs and related theory. Future work is needed to describe the operationalization of the concept in specific C2 situations enabling that concept validity can be tested through case studies and experiments.