The recent intensification of both intersecting inequalities and demands for change calls for an intersectional approach which can account for the complexity of factors and processes structuring social relations, risk and outcomes. Yet intersectionality is thought to be a challenging theory to apply, and represents a puzzle to policymakers and practitioners navigating policy area and equality strand silos. Based on the first empirical study internationally to explore how both practitioners and policymakers themselves understand how to operationalise ‘intersectionality’, this article establishes different ways in which the theory of intersectionality is applied in practice. ‘Intersectionality’ is understood and used in five contradicting ways in UK equality organising and policy, an integral insight because some of these advance intersectional justice while others serve to further entrench inequalities. This typology is proposed as a heuristic to analyse the ways in which intersectionality may be institutionalised in other countries and sectors, and their outcomes, discursive and material.