As ever more corporate social responsibility (CSR) issues compete for space in company reports, and vie for time and attention in the boardroom, companies need to be able to make decisions about which of these issues are really key – for their many stakeholders, for their commercial success and for internal management. Some issues are so important that they demand real recognition and effort by the company – but many other issues do not rise to this level. This threshold is referred to as materiality. Applying it in business is a matter of judgement – and the subject of engagement with stakeholders.