Dirt - obsessively avoided, often misunderstood, but paradoxically also an indicator of 'civilisation' (through production of waste), and a near-magical source of renewable life and medical discovery. History is rich with progressive victories over dirt, from the aqueducts and sewers of the Roman Empire to Sir Joseph Bazalgette's triumphant 'Main Drainage of London' in the mid-nineteenth century, which still functions today. Yet our relationship with dirt is complex and ambivalent. Dirt is waste, excrement, rubbish - but what then is soil? Is cleanliness next to godliness - or sterility? And in a throwaway society, does the battle against dirt depend on an exploited and half-seen underclass of cleaners? Published to coincide with a major new exhibition at the Wellcome Collection in London in March 2011, and lavishly illustrated with images from the Wellcome's archives, this provocative book features specially commissioned essays and a short graphic novel section on the significance and implications of dirt from the microbial level through to the environmental.