CHAOS (Cultural Heritage Archive Open System) is a digital platform for Danish radio broadcasts. Radio broadcasts are an important and vibrant part of our cultural heritage, but providing efficient and effective access to such archives is challenging for lack of a solid digital infrastructure. The Danish LARM project aims to meet this challenge by making one million hours of radio programs available to humanities researchers through the digital platform CHAOS. CHAOS is being built in close cooperation with the researchers involved in LARM. In this paper, we present the user-driven development of the multi-tiered metadata scheme used in CHAOS.