All of engineering can be viewed as a continuation of biology by other means—a metabiological activity. Bioengineering arose relatively recently with specific focus on living systems, for medical purposes in a close alliance with medicine, for scientific and industrial purposes and for other purposes.

A vast array of specializations and subfields have emerged, not always closely related and sometimes predating the overall recognition of bioengineering as a field. An ever expanding and at times confusing and overlapping taxonomy includes biomechanics (encompassing also biorheology and biofluid mechanics), instrumentation, biochemical engineering, bioastronautics, environmental engineering, biomaterials, tissue engineering, biological systems engineering, engineering of drug design and delivery, biotechnology instrumentation, bionanotechnology, and bioinformatics (Blanchard and Enderle 1999, Bronzino 1999, Fung 2001).

Bioengineering, as a field of research and applications, brings to bear not only engineering on medicine and biological organisms, but also a knowledge of biology on engineering designs. This helps assessing...