Spain has introduced some of the toughest restrictions on smoking in public anywhere in Europe.
All smoking in enclosed public spaces has been prohibited - as is lighting up outdoors near a hospital, playground or school.
Spain has a strong cafe culture and the owners of bars and cafes have complained the new law will hurt business reports the BBC.
The anti-smoking rules introduced in 2006 outlawed smoking in the workplace, but it let bar and restaurant owners choose whether or not to allow it. Most chose not to impose any ban.
Only large restaurants and bars were obliged to provide a smoke-free area.
Hotel, restaurant and bar owners have said they could face a 10% drop in trade with the new rules.
The industry has already seen a sharp fall in sales due to Spain's economic problems.
Doctors argue the new law will help smokers give up, something they say is vital when more than 160 Spaniards die each day because of smoking related diseases.