Introduction

By the end of the twentieth century, developed economies have been characterized in multiple ways: information economies, knowledge economies, post-industrial economies, and recently " new economies ". But from a factual standpoint, nothing is as massively evident as the strong and continuous growth, for decades, of the share of services in employment and in GDP (in nominal terms). Now, although economists and social scientists have produced for a long time remarkable works on these activities, on the explanations of their growth, and on the new related economic and social challenges, one can say that the relative weight of the researches on services is still lagging behind the relative weight of services in economic practices. Among the main research topics concerning services, there are those of their productivity (and more generally of their performances) and that of the innovation in services and through services. These two questions are obviously connected, if one admits that medium-term and long-term economic performances are strongly linked to the dynamism of innovation. This double issue is at the center of the present book, stemming from an international conference held in Lille and Roubaix (France) in June 2000 and attended by most of the leading researchers on these topics.