Not if there are children present...
We can't smoke in the office or the pub, but we can still smoke in the car when we're travelling with children.
In this week's Scrubbing Up, the new president of the Royal College of Paediatrics and Child Health says this too should be stopped.
Sometimes you just can't win.
If you act to make people safer, you get accused of introducing the nanny state.
If you let people make their own decisions, you get accused of neglect.
It is admittedly slightly easier when children are involved - we are naturally risk-averse with our own children and by extension with other people's - this is legitimate nanny territory.
But there is more we can do to protect children.
For one thing, we should make it illegal to smoke in cars when children are in the vehicle.
Why on earth would you light up in your car whilst your children are sitting quite happily in the back?
On the assumption that you wouldn't pass the packet round and invite the kids to light up, why make them breathe tobacco smoke at all?
You can't inflict this on your colleagues at work any more. Why should we treat our children's health as a lower priority than our employees?
Unfortunately, parents in the UK have smoked around their children for generations.
My parents put me and my brothers and sisters in the back of their car, started their three hour journey and lit up cigarette after cigarette - often with the windows closed.
What can we learn from experience elsewhere?
Health warnings on cigarette packets were initially met with scepticism
Recent research published by the Ontario Tobacco Research Unit showed that with drivers smoking just one cigarette, the pollution created inside the car was 100 times greater than the US Environmental Protection Agency accepted standard for fine particle exposure.
New Brunswick is the latest province in Canada to introduce legislation banning smoking in cars with children.
This change in legislation will prohibit smoking in a car when there is a child under the age of 16 in it.
Extremely sensible, common sense - but seen by some as too draconian and the trickling of nanny state rules again.
Second-hand smoke has been found to be strongly linked to chest infections in children, asthma, ear problems and sudden infant death syndrome, or cot death.
We should be making cars totally smoke-free if there are children travelling in them.
'Not all bad'
Let's follow the others who seem to have done it successfully - California, South Australia and Cyprus.
This would be a piece of progressive legislation and we would quickly realise the benefits as with other extremely successful motoring interventions - seat belts, mobile phones and drink-driving.
Looking at our attitudes and behaviour around smoking, we should always consider the health issues related to our actions, the example we are setting and the consequences that our behaviour may have on our children throughout their adult lives.
Smoking at work was seen as normal a few years ago and now as incredibly intrusive, not the norm.
Of course, it's not all bad here and good elsewhere.
We do lead the way in many areas of child health - the UK is second best in the Unicef league table for accidental child deaths, with child injury death rates below seven per 100,000.
But we need to look at the health outcomes and effects of the bad things that adults do to their children.
I know many of you will disagree with me - perhaps strongly.
Most changes designed to make life safer - seat-belts in cars, health warnings on cigarette packets - were initially met with scepticism or even derision when they were first proposed.
Those of us in the medical profession, who see the results of passive smoking first hand, need to be ready to lead and make a convincing case.
Only then can we hope that necessary measures are viewed not as the 'nanny state' but as 'common sense'.