This books provides new research on the theories and applications of complex systems. Chapter One reviews the process algebra approach to quantum electrodynamics. Chapter Two describes a specific aspect of complex systems and the fact that they may consist of established subsystems or components that originate from converging industries. Chapter Three examines the development of the generalised nonlinear Schrödinger equation of rotating cosmogonical body formation. Chapter Four analyses the application of neural network modeling in organising a hierarchical teaching system based on mentorship. The final chapter presents two methods to evaluate the collaborative potential of a network of 16 organisations and identifies measures to promote their coordination.