Abstract: Apparatus for superplastically forming large parts from titanium comprising: a furnace (10) having an interior, the inside surface of the furnace (10) being contoured and finished so as to form a mold for the part to be superplastically formed; means (70) for heating the interior of the furnace (10); and a supply (60) of an inert gas. The surface of the mold is adapted to receive a substantially unformed titanium blank (80). The heating means (70) is adapted to heat the titanium blank (80) to the required temperature for superplastic forming. The supply (60) of the inert gas is operable to exert a pressure onto the surface of the titanium blank (80) furthermost from the surface of the mold such that the inert gas causes the titanium blank (80) to deform and take up the shape of the mold, thereby forming the required part.