Jet-skiers are putting lives at risk by anti-social use of their machines, Tenby's police chief warned this week.
Now that the good summer weather has arrived, officers in the county have been receiving complaints from beach users about problems around the coastline.
The main complaint is that jet-skiers are using areas predominantly used by swimmers, some of them youngsters, thereby placing them at risk of serious injury or possibly worse.
The beaches of Pembrokeshire are for all to enjoy and jet-skiers must observe the following simple by-laws.
Jet-skis are not allowed to operate within 100 metres off any beach, except for the purpose of launching or returning to land. When launching or returning to land, the maximum speed should not exceed eight knots.
Pembrokeshire County Council have produced a water craft and speed boat code of practice, which is available from the council on request.
Inspector Les Clark, of Tenby Police Station, said: "I would implore jet-skiers to be sensible and not place our young people at risk.
"Jet-skiing is fun, but the use of these machines should not spoil other people's enjoyment of the beach.
"Get a copy of the code of practice and please abide by it."