“…Knowledge-based economic activities, particularly high-tech firms, have a strong tendency to cluster, primarily around metropolitan locations and in the satellite urban ring around the main metropolitan area (see, for example, Bar-El & Parr, 2003;Capello, 2002;Cooke & Schwartz, 2003;Frenkel, 2001;Frenkel & Shefer, 2001;Schwartz, 2006). The main factors behind such a concentration include knowledge accumulation and knowledge spillovers, relational capital, tacit knowledge, external learning and processes of knowledge acquisition, and innovation networks, as described briefly in this section.…”