Answer:

When visiting someone’s home, the smoker should glance around the room first. If there is no ashtray, that is a cue that smoking is not allowed. Don’t even ask permission.

When smoking is not allowed in a home, the guest should be offered an alternative. The host or hostess might say, “I would rather you didn’t smoke in here, but you are welcome to step out on the back porch (in the study, on the balcony) if you’d like.”

If smoking is allowed in the home, it is still courteous to ask, “Mind if I smoke?”