From colourful Victorian trade cards of the 1870s to the All Blacks half time commercials of today, advertising has gone from a small component of everyday life to a ubiquitous presence.

Perhaps the most easily recognizable advertising medium of the late 19th and early 20th centuries is the enamel/porcelain sign. Manufacturing started as early as the 1880s, companies saw the advantages of enamel as a material that was both durable and weather resistant. Although these signs were first made in Germany, the manufacturing technique soon spread around the world, where their bold colours and eye-catching graphics were put to good use advertising cigarettes, motor oil, kitchen ingredients and soaps to name a few. With the onset of World War II, however, many of these signs were destroyed for the base metal they contained. Their resulting rarity makes them attractive to collectors.

Tin signs have also been used since the late 19th century; they became more popular after the war, and were often produced as a cheap alternative to enamel signs. Unlike their enamel companions, however, tin signs are prone to rust and degradation making good ones harder to find.

It is now illegal to produce enamel signs in New Zealand and most western countries due to the techniques used and health problems that can come from the process.