Early modern books were printed with a large variety of different fonts. In the first decades after Gutenberg’s invention, every printer had to start out by cutting his own punches and casting his own fonts. This diversity was somewhat standardised with the advent of an organised font trade in the 16th century. However, this was a very long process and one that was not completed before the 19th century. Only then did industrialised mass production make fonts as stable and - at least for text fonts - predictable as we know them today. The diversity of fonts is one of the cornerstones of analytical bibliography: with detailed descriptions of the individual fonts we can identify the printer of almost any given incunabula or at least narrow the possible candidates down to a very small group.