The legal age for buying cigarettes in Scotland is to rise from 16 to 18 next month.
The minimum age to buy cigarettes would be raised to 18
MSPs unanimously backed a change in the law following a short parliamentary debate.
The move attracted cross-party support and will also take place in England and Wales from 1 October.
However, concerns have been raised that extra resources would not be made available in time for the imposition of the law.
Health Minister Shona Robison told members that a person who started smoking at the age of 15 was three-times more likely to die from its effects than someone taking up the habit in their 20s.
The legal age for buying cigarettes was set prior to World War II, long before the health threats posed by tobacco were recognised.
Ms Robison said that more must be done to combat smoking despite a series of measures such as the ban on smoking in enclosed public places.
But the Liberal Democrats questioned the effectiveness of the move as only 11 prosecutions have been successful against shops selling tobacco to children under 16.
The Tories said councils must have more resources to make the new age limit effective.