I am a community nurse, and many of my patients smoke. The ones that smoke in my presence are mainly people who need assistance to light a cigarette eg MS sufferers. It is a small pleasure that these people have and I would never grudge it. My NHS trust's view is that it is the patients home and we have no right to ask them not to smoke. I agree. But the carers for the local authority are making a huge fuss about it. I have a feeling that most people, if asked politely, would oblige you and wait until you have left. They are so used to lighting up in their own home, they just don't give it a second thought.