Real-world engineering problems often require concurrent optimisation of several design objectives, which are conflicting in most of the cases. Such an optimisation is generally called multi-objective or multi-criterion optimisation. The area of research that applies evolutionary methodologies to multi-objective optimisation is of special and growing interest. It brings a solution to many yet-opened real-world problems and questions. Generally, multi-objective engineering problems have no single optimal design, but several solutions of equal efficiency allowing different trade-offs. The decision maker's preferences are normally used to select the most adequate design. Such preferences may be dictated before or after the optimisation takes place. They may also be introduced interactively at different levels of the optimisation process. Multi-objective optimisation methods can be subdivided into classical and evolutionary. The classical methods usually aim at a single solution while the evolutionary methods target a whole set of so-called Pareto-optimal solutions. The aim of this book is to provide a representation of the state-of-the-art of the evolutionary multi-objective optimisation research area and related new trends. Furthermore, it reports many innovative designs yielded by the application of such optimisation methods. The contents of the book are divided into two main parts: evolutionary multi-objective optimisation and evolutionary multi-objective designs.