In his book Well-Being and Fair Distribution, Matthew Adler advances a sustained and comprehensive argument for a certain variety of prioritarianism. This essay provides a critical overview of the book. The main criticisms made are the following. First, the ‘intersection’ approach adopted by Adler, in order to allow incommensurability in well-being, may have problematic consequences. Second, that Adler’s preferred form of prioritarianism must be restricted to non-negative utilities may be a more serious limitation than he appreciates; and there may be preferable forms which avoid this restriction. Third, Adler’s case against the Ex Ante Pigou Dalton principle might be bolstered by re-evaluating the force of ex ante claims.