Trust in institutions is declining across most democracies, which makes this an unusually live subject for a research organisation rather than a purely theoretical one. Legitimacy is the question of why people accept authority, sitting underneath every argument about institutions, elections, courts and international bodies. It’s central in political theory and increasingly practical. The word has commercial uses too. Authentication, verification, credentialing and anti-counterfeiting all trade in legitimacy in the literal sense, which is a real technology market.