A police force has become the first in Britain to allow officers to smoke e-cigarettes.
The electronic inhalers have been banned by some organisations amid fears they're still bad for health.
They turn a liquid solution into safe smoke and contain a small amount of nicotine, but not the dangerous tar.
Cambridgeshire Constabulary has now decided that staff can smoke them, saying their benefits outweigh the disadavantages.
A force spokesman said: "Following discussion which considered both pros and cons of both visibility and health it was agreed that use of electronic cigarettes would be permitted on police premises although not in front-facing areas such as enquiry offices."
However Addenbrooke's Hospital in Cambridge has banned e-cigarettes from their premises.
E-cigarettes were first invented in China in 2003 to combat smoking bans and are designed to give the same sensation as a regular cigarette.