1. Introduction, A. Illanes. 2. Enzyme Production, A. Illanes. 3. Homogeneous Enzyme Kinetics, A. Illanes, C. Altamirano, L. Wilson. 4. Heterogeneous Enzyme Kinetics, A. Illanes, R. Fernández-Lafuente, J.M. Guisán, L. Wilson. 5. Enzyme Reactors, A. Illanes, C. Altamirano. 6. Study Cases of Enzymatic Processes. 6.1. Proteases as catalysts for peptide synthesis, S. Barberis, F. Guzmán, J. López-Santín. 6.2. Synthesis of ß-lactam antibiotics with penicillin acylases, A. Illanes, L. Wilson. 6.3. Chimioselective esterification of wood sterols with lipases, G. Alvaro, A. Illanes. 6.4. Oxidoreductases as powerful biocatalysts for green chemistry, J.M. Guisán, R. Fernández-Lafuente, L. Wilson, C. Mateo. 6.5. Use of aldolases for asymmetric synthesis, J. López-Santín, G. Alvaro, P. Clapés. 6.6. Application of enzymatic reactors for the degradation of highly and poorly soluble recalcitrant compounds, J.M. Lema et al.