This article argues that the writings of T. H. Marshall contain not one, but two, theories of citizenship, and there is a problem about whether they are compatible with one another. The second, less familiar, theory is mainly developed in Marshall's later works, especially The Right to Welfare, but many of its essential features can be found in Citizenship and Social Class, although not in the sections of that work which are most frequently quoted. Several areas where Marshall's shifting views contributed to this second version of citizenship are discussed: citizenship as national membership and as a body of obligations, the reality of social rights, discretion versus enforceable entitlements, citizenship as a bearer of its own inequalities, the relationship with the capitalist class system. Increasingly, Marshall came to restrict citizenship to the political sphere, thereby endorsing a conventional liberal view: but then he was, it is argued, in many respects a pretty conventional liberal. The article concludes by noting the paradox that much of the current interest in Marshall's thought is because a ‘strong’ view of citizenship is attributed to him which he may never have held, and which he certainly relinquished towards the end of his writing career.