Substance is a double-disc set collecting New Order's singles, including several songs that were never available on the group's albums, at least in these versions. While there are a couple of re-recordings of earlier singles, most of Substance consists of 12" single mixes designed for danceclub play. Arguably, these 12" mixes represent New Order's most groundbreaking and successful work, since they expanded the notion of what a rock & roll band, particularly an indie rock band, could do. Substance collects the best of their remixes, and in the process it showcases not only the group's musical innovations, but also their songwriting prowess -- "Temptation," "Blue Monday," "Bizarre Love Triangle," and "True Faith" are some of the finest pop songs of the '80s. Although it is a double-disc set, Substance isn't overly long. Instead it offers a perfect introduction to New Order, while providing collectors with an invaluable collection of singles.