William Latham Christian Le Bas Persistence of firm invative behavior became an important topic in applied industrial organization with the publication of the seminal empirical work of P. Geroski and his colleagues (1997). Evidence that firms invate persistently has led previous studies to focus on the determinants of invation persistence and on its heterogeneity across industries, techlogies and countries. The aims of this book are: (1) to illumine the scale and scope of the phemen of persistence in invation, and (2) to account for the principal factors that explain why some firms invates persistently and others do t. Because this book deals intensively and extensively with the subject of firm invation persistence, which is t, as yet, a well-kwn term, we need to provide a ntrivial definition of it that encompasses the full range topics we want to address and aids our understanding of how they are related to each other. We begin with a careful identification of invation. Our first definition is drawn from K. Pavitt (2003), invation processes involve the exploration and exploitation of opportunities for a new or improved product, process or service, based either on an advance in technical practice or a change in market demand, or a combination of the two. While this definition is clear, and conforms well to both our empirical and theoretical perspectives, some elaboration may help to clarify the concept.