Migration has become a defining feature of contemporary British society, influencing demographic structures, labour markets, public services, cultural identities and debates surrounding social cohesion. Britain has developed a complex multicultural society shaped by post-war migration from former colonies, European mobility, humanitarian migration and more recent international movements associated with education, employment and family reunification. This paper examines the relationship between migration, multiculturalism and social integration in contemporary Britain from a comparative global perspective. It explores how migration has influenced British society and analyses competing approaches to multiculturalism, integration, citizenship, cultural participation and social cohesion. Particular attention is given to education, employment, housing, language acquisition, political participation and everyday social interaction as important dimensions of integration. The paper also compares Britain\'s experience with selected approaches in Canada, Australia, France and Germany, highlighting differences in citizenship models, cultural recognition, language policies and institutional responses to migration. The analysis suggests that integration is multidimensional and cannot be adequately measured through cultural assimilation alone. Economic participation, equal access to institutions, social interaction, civic participation and a sense of belonging are interconnected components of integration. At the same time, outcomes vary considerably across migrant groups and generations, reflecting differences in migration histories, socioeconomic circumstances, educational opportunities and local contexts. The paper concludes that contemporary British migration policy and multicultural practice should be understood through the interaction of demographic change, institutional structures and everyday social relations rather than through a single model of integration.