The De Morgan Medal is a prize for outstanding contribution to mathematics, awarded by the London Mathematical Society. The Society's most prestigious award, it is given in memory of Augustus De Morgan, who was the first President of the society.
The medal is awarded every third year (in years divisible by 3) to a mathematician who is normally resident in the United Kingdom on 1 January of the relevant year. The only grounds for the award of the medal are the candidate's contributions to mathematics.