Five years ago the Spanish government introduced a ban on smoking in public places - as did many other countries around that time. Of course, being Spain it wasn't quite so clear cut. Although smoking was banned in all indoor workplaces, places of entertainment, shops, hotels, bars and restaurants, and other enclosed places, not to mention public transport, owners of bars and restaurants with a floor area of 100 sq metres or less were permitted a discretion; they could decide along with their customers whether to apply the ban or not. This is why you could be forgiven for thinking that there is no such ban in Spain. The great majority of bars/restaurants were, or considered themselves to be, less than 100 sq metres, and the owners quite correctly presumed that their smoking customers would prefer to carry on as usual.
Not, however, for very much longer. A revised law has now passed all its hurdles and will come into effect on January 2nd 2011. Smoking will then be completely prohibited in all enclosed public spaces - defined as "all places accessible to the public or for common usage, whether publicly or privately owned." The only concessions are that hotels may set apart 30% of their rooms for smokers, as long as they are completely separated from the remaining rooms (probably, 'smoking floors'), and the outdoor areas of prisons, psychiatric clinics and centres for the elderly or disabled.
It will be interesting to see how it goes.