The purpose of this chapter is to provide a detailed overview of the UK legal and institutional factors at the macro-level that can be regarded as decisive for explaining the effective capacity of the country to integrate migrants, refugees and asylum seekers into the labour market. By doing so, we aim to better understand the conditions within which integration policies for migrants, refugees and asylum applicants (MRA) may take place. We begin by providing an insight into the social and cultural context of migration in the UK, firstly by looking at the history of migration and the social and political instabilities of the country. Furthermore, we investigate how legislation concerning migration and asylum has developed within the UK context across the decades and analyse how legislation has been translated by UK policymakers in recent years. We then examine the current constitutional organisation of the British state, highlighting the importance of case law in developing MRA integration. Following this, we outline key legislation concerning the integration of MRA in the British labour market. The chapter then provides a critical overview of the integration strategies (or the lack thereof) promoted at the national level, outlining the institutional challenges that affect integration. We then conclude by highlighting the possible impact that Brexit will have on an already ‘hostile environment’ for migration.