Volcanic debris avalanches (VDA) are, on the one hand, stunning natural phenomena, but, on the other, can pose serious threats to people and infrastructure. This first chapter aims to introduce a collection of themed papers gathered in a book, each illustrating the advancements of a different aspect of VDA research. As a state-of-the-art collection, the 11 papers provide a powerful tool for the volcanological community to enhance our understanding of their history and global distribution, collapse initiation and cyclic occurrence, problems with terminology, transport processes and deposit characteristics, climate impacts, application of numerical tools, and the records of marine and ringplain settings.