Boundary Integrable Quantum Field Theories

These lectures concerned the properties of quantum field theories in the presence of boundaries. There are many different approaches to this subject. One can begin by studying conformal field theories with boundaries - the principal theme of the lectures at this school by Jean-Bernard Zuber and by Christoph Schweigert - and then, as described in Gérard Watts' lectures, consider their perturbations. In many cases these perturbations result in massive integrable quantum field theories, and it was the direct study of such theories in their own right that formed my main topic. A number of reviews of this subject can be found on the electronic archives, and so in this contribution I shall restrict myself to an outline of the questions touched on in my talks, and a brief list of references to which the interested reader can turn to find at least some of the answers...