This is the fourth volume in the series, which begun publishing in 2003 and forms an overview of Roman Signer's work. Signer's materials-water, fire, air and earth-are elements that intervene in the design of the work and complete it (Roman Signer). Making its production visible is usually part of his work. The artist himself comments on almost all of the 700 sculptures and actions, without interpreting them. He states facts such as technical details, climate, the sequence of events and thus gives the reader a precise impression of his work, almost elevating them to observer of the action. The result is a catalogue raisonné and an autonomous account of the work in this unique oeuvre.