【正文】 nments. The author suggests expanding the concept of cluster to microcluster, the socalled diagonal cluster (diagonal integration in Poon, 1994),??labelled in this way to refer to the concentration of plementary (or symbiotic) firms, which each add value to the activities of other firms, even though their products may be quite distinct. In this sense, diagonal clustering brings together firms that supply separate products and services, effectively creating a bundle that will be consumed as though it was one item. For tourism and other service industries, this is often routinefor example, a tourism destination requires firms to supply the activity, provide transport, hospitality, acmodation, etc. The colocation of many plementary providers adds value to the tourism experience, and the converse may also be true, in that the absence of key services restricts the development of other firms?? (Michael, 2021). In essence, a firm producing a plementary product or service is not a petitor, because its activities add more value to the product than the product alone. Thus, cooperation creates alliances and works, makes better use of skills and resources and encourages innovative business activities which improve local development. The diagonal cluster theoretical framework can also be useful as an interpretive model for the local development of convention destinations. It is a particularly interesting model to apply in the case of Italy because it supports the main guidelines defined by national tourism legislation. The national legislation reform on tourism defines the Tourism Local System (TLS) as ??homogeneous or integrated destinations, also concerning areas which belong to different regions, characterised by an integrated supply of cultural and environmental goods and tourism entertainments, including typical agricultural products and local arts and crafts, or by a wide presence of single or cooperating tourism enterprises?? (Law nr. 135,2021). As the TLS definition reflects cluster theoretical paradigm in the cooperation, integration and homogeneity principles of the Italian tourism industry, this might be useful in exploring some interesting questions. Do groups of destinations exist with homogeneous tourism characteristics? In TLSs, do local subsystems specialised in different hosting segments, such as the convention segment (CLS), coexist? Are these subsystems integrated with each other? What are the main local features supporting a convention and tourism work? Which destination factors encourage future CLS growth and support emerging clusters? What exists or should exist in a destination in order for convention works to develop? In answer to these questions, we can use the theoretical model proposed by Porter (1998).In his diamond model of petition, the Author essentially focuses on four ponents of petitive advantage: (1) demand conditions in terms of the quality, level and nature of tourist interest。 (2) local factor conditions, such as a region?s natural resources and location。 (3) tourismrelated and supporting industries, including acmodation, food and beverage outlets, tourist attractions, the transport sector and various government agencies。 (4) government policy supporting munities with information and infrastructure, facilitating inputs such as an educated workforce, maintaining an appropriate framework for regulation of standards and ensuring macroeconomic and political stability. Such a conceptual model could be usefully applied to tourism and convention destinations. The principles of the diamond model can be bined with cluster theory to provide a more prehensive and balanced approach to regional economic development and the role of tourism within it. However, the conceptualisation of the sectors involved in tourism works and the nature of their interrelationships in a cluster is not easily standardized. The plexity of the cluster concept suggests that no single definition or methodology is universally correct but varies depending on the economic sector analyzed and on its strategic practices and policies. Considering the main aims of the paper, we have decided to focus on some of the key aspects of tourism and convention destinations: hospitality, acmodation, convention services, educational institutions, transport, population and local resources (Fig. 1). Our original conceptual model is the basis for designing an empirical methodology. Fig 1. The proposed conceptual model of locational petitive advantage in convention clusters The empirical analysis is conducted in two steps. Firstly, we suggest using the statistical technique of Cluster Analysis for identifying the municipalities with similar tourism and convention supply and locational resources. This statistical method enables the identification of the different typologies of CLSs and the evaluation of characteristics of CLSs that are in different stages of their convention production life cycle. Secondly, Quantile regression models are introduced to estimate the impact of local characteristics on the convention industry