Londoners are to be asked whether they want to follow New York's example and ban smoking in public places.
Doctors have already called for a ban on public smoking
They will be asked whether more restrictions should be imposed in London's cafes, shopping centres, taxis, restaurants, pubs and stations.
The London Health Commission, which advises mayor Ken Livingstone, is running the Big Smoke Debate - described as one of the UK's biggest consultations on a public health issue.
It follows a Mori poll of 221 Londoners which found 71% were bothered by other people's smoke in enclosed public places.
The cities of Sheffield, Birmingham and Brighton are considering bringing in more restrictions.
Mr Livingstone said he wanted to work with businesses to increase access to smoke-free venues.
Organisers say it is not about whether people should smoke, but where it should be allowed.
The poll will run until the end of the year and the results will be given to Mr Livingstone and LHC members in January.
Questionnaires will be in the mayor's newsletter, The Londoner, which is delivered to all households in London.
Those with internet access can log on to the Big Smoke Debate website.