This textbook provides a detailed analysis of operation and planning problems faced by virtual power plants participating in different electricity markets. The chapters address in-depth, topics such as: optimization, market power, expansion, and modelling uncertainty in operation and planning problems of virtual power plants. The book provides an up-to-date description of decision-making tools to address challenging questions faced by virtual power plants such as: How can virtual power plants optimize their participation in electricity markets? How can a virtual power plant exercise market power? How can virtual power plants be optimally expanded? How can uncertainty be efficiently modelled in the operation and planning problems of virtual power plants? The book is written in a tutorial style and modular format, and includes many illustrative examples to facilitate comprehension. It is intended for a diverse audience including advanced undergraduate and graduate students in the fields of electric energy systems, operations research, and economics. Practitioners in the energy sector will also benefit from the concepts and techniques presented in this book. In particular, this book: Provides students with the GAMS codes to solve the examples in the book;  Provides a basis for the formulation of decision-making problems under uncertainty; Contains a blend of theoretical concepts and practical applications that are developed as working algorithms.