The adhesives most widely used in conservation (epoxies and polyesters) have the serious disadvantages of irreversibility, excessive bond strength, and discoloration of the original material. Thus, to treat two objects from the W.R. Hearst collection, the author selected methyl methacrylate. It was selected after comparative applications and physical testing showed it to be easily reversible, weaker in bond strength than the original material (an Egyptian stone head, of black granite, and a Persian wall panel, composed of thick terracotta tiles). This paper describes the tests comparing the methyl methacrylate (Technovit 4004) as to viscosity, pot life, sheer strength, and reversibility, to five other typically used adhesives: Ablebond 342-1 (epoxy); Akemi (polyester); Araldite 502 (plasticized epoxy); Araldite 6010 (epoxy); and HXTAL NYL-1 (epoxy). It gives a detailed account of its application. Acknowledgements and list of materials and suppliers are appended.