The aim of this introductory chapter is to account for the major advances made in “Service Innovation Studies” (SIS) – and above all to provide an agenda setting out research priorities in this area. The chapter is broadly organized into five sections. In the first, we outline the 15 main advances achieved in the SIS field over the past two decades, which fall into two distinct but linked groups: on the one hand, advances in theoretical conceptions, and, on the other, advances in innovation modes and institutional arrangements. In the next three sections, we examine the 15 main challenges that could structure our research agendas over the next decade, distinguishing between societal challenges (e.g. environmental, population ageing, gender challenges), organizational and structural challenges (e.g. entrepreneurship, smart service ecosystems) and methodological and didactic challenges (multidisciplinarity, evaluation, education). The last section is devoted to the conclusion, along with a short presentation of the contents of the book.