Rescue services try to tackle tombstoning
2 August 2011 Last updated at 09:36 BST
The practice of tombstoning - jumping off high cliffs or piers into the sea unsupervised, is causing concern.
The rescue services say a least 14 people have died as a result of it in the last five years.
There are concerns many people are still ignoring warnings about the risks.
Mark Bell from the RNLI in Brighton explained to the BBC's Graham Satchell what they are doing to try and stop people tombstoning.