Over the past eleven years, the British government has passed a number of laws that specifically tackle, or include directly in their provisions, protection of the freedom of ‘religion or belief’ – based on the right to hold or not to hold religious or other philosophical beliefs. This paper looks specifically at how ‘religion or belief’ is defined, particularly in relation to the Equality Act 2006 / 2007, and locates this within the wider policy-led and academic attempts to define ‘religion’. Looking at some of the implications of the definitions applied, it goes on to summarise key elements of current law on non-discrimination, drawing on public sources and examples from the Equality and Human Rights Commission. Nothing in this background paper constitutes legal advice or should be read as constituting such advice. If you have legal questions or requirements, please consult a qualified lawyer.