 Alumni total over 160,000, covering over 190 countries with more than 80 active alumni groups.The LSE Students' Union (LSESU) is affiliated to the National Union of Students and is responsible for campaigning and lobbying the School on behalf of students as well providing student support and the organisation and undertaking of entertainment events and student societies.It is often regarded as the most politically active in Britain – a reputation it has held since the well documented LSE student riots in 1966–67 and 1968–69, which made international headlines.