Strong Ale, or 'Wee Heavy', was in the same strength category as barley wine. Both had a very high alcohol content: a 90/- ale in the early 19th century had an original gravity as high as 1.125, and a final gravity of 1.055: approximately 9% alcohol by volume.

At this time, roughly 10% of this beer was exported, with volumes and destinations being dictated by colonial expansion. In 1815 important strong ale export markets included:

By 1850 the market had expanded to include

There had been nearly 50 brands of Scottish ales from almost 20 brewers on the market in 1960; by 1991 there remained only 6 brewers producing less than 20 brands.