Over the past 50 years there has been an increase in the numbers of people jumping/falling in front of trains on the London Underground system. Case-fatality rates have fallen from 70% in the 1950s to 55% today. The proportion certified as suicide has fallen while the proportions certified as accidents or open verdicts have risen. There is unusual clustering of events at some stations which are adjacent to psychiatric units. The hypothesis that ease of access to London Underground stations may sometimes be a determinant of suicide is investigated.