In recognising an urgent need to move beyond case studies and develop a conceptual synthesis, the scope of this volume is broad, covering the principal elements of both the invasion process and human responses to seaweed invasions. This includes addressing legal frameworks for regulatory control, practical means to track and respond to invasive seaweeds in the field, as well as the ecology of invasions. The result is both a valuable multidisciplinary synthesis of work to date, and a pointer to future challenges and priorities.