among political and administrative officials" of Mitteldeutschland.) Types By composition Following development of the concept of interorganizational networks in Germany and practical development of clusters in the United Kingdom; many perceive there to be four methods by which a cluster can be identified: Geographical cluster – as stated above e.g. the California wine cluster or the flower cluster between Rotterdam and Amsterdam in the Netherlands. Sectoral clusters (a cluster of businesses operating together from within the same commercial sector e.g. marine (south east England; Cowes and now Solent) and photonics (Aston Science Park, Birmingham)) Horizontal cluster (interconnections between businesses at a sharing of resources level e.g. knowledge management) Vertical cluster (i.e. a supply chain cluster) It is also expected – particularly in the German model of organizational networks – that interconnected businesses must interact and have firm actions within at least two separate levels of the organizations concerned. By type of comparative advantage Several types of business clusters, based on different kinds of knowledge, are recognized: High-tech clusters – These clusters are high technology-oriented, well adapted to the knowledge economy, and typically have as a core renowned universities and research centers like Silicon Valley, the East London Tech City or Paris-Saclay. An exceptional example of a prominent high-tech cluster that does not include a university is the High Tech Campus Eindhoven, located in the Dutch city of Eindhoven. Historic know-how-based clusters – These are based on more traditional economic activities that maintain their advantage in know-how over the years, and for some of them, over many centuries. They are often industry-specific. An example is London as financial center. Factor endowment clusters – They are created because a comparative advantage they might have linked to a geographical position. For example, wine production clusters because of sunny regions surrounded by mountains, where good grapes can grow. This is like certain areas in France such as Burgundy and Champagne, as well as Lombardy, Spain, Chile and California. Low-cost manufacturing clusters – These clusters have typically emerged in developing countries within particular industries, such as automotive production, electronics, or textiles. Examples include electronics clusters in Mexico (e.g. Guadalajara) and Argentina (e.g. Córdoba). Cluster firms typically serve clients in developed countries. Drivers of cluster emergence include availability of low-cost labor, geographical proximity to clients (e.g. in the case of Mexico for U.S. clients; Eastern Europe for Western European clients). Knowledge services clusters – Like low-cost