What is Keystone sector

This chapter is written to describe a different vision on how to make use of a simple network diagnosis instrument in order to identify and describe the network structure of a set of diversified institutions located and acting in a regional environment. The use of this analytical framework enables policy makers to intervene in a variety of manners. After a detailed literature review of different discipline approaches, we describe different models for network formation and present the keystone sector analysis as a parsimonious centrality measure existing before more recent and complex frameworks used in reduction crime policies with the same definition (e.g. inter-optimal centrality). Considering the embeddedness in social network environments where different institutions – private, public, third sector – make decisions and influence future decisions, the keystone sector analysis is also helpful to uncover some methodological weaknesses in socioeconomic development and provide new opportunities for policy purposes.