Interleukin-18 binding proteins which are capable of binding IL-18 and of modulating and/or blocking IL-18 activity are provided. Methods for the isolation and recombinant production, DNAs encoding them. DNA vectors expressing them, vectors useful for their expression in humans and other mammals, antibodies against them are also provided. Therapeutic uses of IL-18 binding proteins and further inhibitors of IL-18 are also provided according to the invention.