Until recently waste production was seen as an inevitable outcome of industrial production and processing, and a problem that could be managed by end-of-pipe and in situ biotreatment, disposal, or simply be ignored. However the introduction of clean, or cleaner, technology options now is focussing attention on the minimisation of materials and energy use, and waste generation, and upon recycle. Thus clean technology has emerged as a concept that is compatible with industrial sustainability, and whose environmental benefits and economic competitiveness have been demonstrable over a range of industrial sectors. Biotechnology is an enabling technology that offers one important route to clean products and processes; it provides powerful and versatile tools that can compete with chemical and physical means of reducing both material and energy consumption, and the generation of wastes and emissions. The wide penetration of biotechnology in industry has still to occur but many examples of its ability to deliver clean and competitive products and processes are now available particularly through the development and application of biocatalysts. The introduction of clean or cleaner processing does not necessarily entail a complete change in manufacturing strategy or the refitting of plant. Upgrading existing manufacturing processes by fitting biotechnology unit stages illustrates the opportunities for such intermediate technology. Nevertheless, for biotechnology to achieve its full potential as a basis for clean industrial products and processes beyond its current applications, innovative R&D will be needed. The successful application of biotechnology as a clean technology is illustrated in this review through a series of case studies, while the innovative nature of biotechnology in this context is demonstrated by the development and application of novel biocatalysts.