Proceedings of the International scientific and practical conference ―Science in the Modern World‖ (May 4-6, 2026) / Publisher website: www.naukainfo.com. – Barcelona, Spain, 2026. - 260 p.

96 Data from the OECD indicate that the share of the foreign-born population reached approximately 18.4% in 2024, reflecting a profound demographic transformation [8]. Structurally, migration to Spain is predominantly family-based and intra- European: around 39% of migrants are admitted through family reunification, 32% are EU citizens, while labor migration accounts for only about 6% [8]. This distribution points to a shift toward long-term and more stable forms of migration. The classical push–pull framework remains a foundational approach to explaining migration processes; however, contemporary scholarship has significantly expanded and refined this model. Migration flows are now understood as exhibiting nonlinear dynamics, shaped not only by economic differentials but also by state policies, transnational social networks, and the cumulative presence of migrant communities. These factors generate a self-reinforcing mechanism, whereby established migrant networks facilitate and stimulate subsequent migration flows [9]. In this context, the concept of a ―critical threshold‖ of integration is particularly relevant. It suggests that once migrant communities reach a certain level of concentration, the process of social adaptation accelerates, leading to qualitative changes in integration dynamics [1]. Migration also constitutes a key driver of economic growth in Spain. Empirical evidence indicates that migrants play a crucial role in sectors experiencing persistent labour shortages, including agriculture, construction, and services [8]. In this sense, migration functions as a structural mechanism compensating for labour deficits within the national economy. Beyond labour market contributions, migration positively affects external economic relations by reducing transaction costs and strengthening transnational trade networks [6]. At the same time, however, the labour market exhibits clear patterns of segmentation: migrants are disproportionately concentrated in lower- skilled and lower-paid sectors, which constrains their opportunities for upward social mobility.