As governments around the world embrace austerity, one of the key arguments they use is that the welfare state is unaffordable. Paying for the Welfare State in the 21st Century shows that argument to be specious, relating current debates about taxation and welfare to a deeper understanding, informed by political economy, of the relationship between taxation and spending on social services. Only by understanding the critical functions of welfare in post-industrial society can we legitimately consider what levels of taxation and support are reasonable.