Abstract The use of biochemical engineering in an industrial setting is presented by examples from the author's own field of expertise: process development for industrial enzymes. Examples given cover the fields bioreactor performance, measurement and control on fermentation, downstream operations and development and optimization of production strains. The use of engineering principles is placed in the industrial context of a high focus on development speed, fast product turnover and competing ‘technologies’ such as empirical testing, parallel conclusions. Finally the overall applicability of engineering principles is reviewed in light of the industrial aspects of process development: existing production equipment, production facilities of varying age, choice of expression system and overall product economy.