The rapid world-wide growth of the biotechnology industry has been based on the development of genetic engineering and cell fusion techniques, by which proteins having valuable diagnostic, therapeutic, industrial and other applications can be produced in commercial quantities. Qlone is a major Australian biotechnology company specializing in the development of novel products for the human and animal health care markets using innovative technology in cell culture and recombinanat DNA techniques. Qlone has designed and built a unique modular production facility to ensure that Qlone products are produced according to cGMP (curent Good Manufacturing Practices) and will satisfy the stringent requirements of the United States, European or Australian regulatory authorities. The development of the monoclonal antibody (Mab) conjugate has revolutionized cancer detection and therapy. Conjugation of Mabs to cytotoxins such as ricin A or diptheria toxin has resulted in the most potent cytocidal substances known. A large number of murine Mabs directed against tumour-associated antigens have recently been developed in laboratories both in Australia and abroad. Many of these Mabs and Mab conjugates are in clinical trial stages. There is an increasing demand for therapeutic-grade Mabs produced according to cGMP which satisfy the United States Food and Drug Administration and Australian regulatory guidelines.