In the modern chemical industry the aim is to achieve high-quality products and minimise unwanted by-products. Selectivity in the reactor is particularly important in processes in which by-products cause environmental problems (e.g. NOx and CO in exhaust gases from automobiles). In processes where very high purity is required for legislative reasons, such as in the pharmaceutical industry, the cost of purification becomes important and reactor performance is of vital significance. Knowledge of the advantages and drawbacks of chemical reactor properties is therefore essential for all chemical and biochemical processes. Research in chemical reaction engineering includes the kinetics and dynamics of chemical and biochemical processes coupled with molecular mass transport phenomena. Other important research fields are turbulence modelling linked to chemical reaction, fermentation processes, catalyst deactivation, process control, stability and optimisation.