Cytochrome P450 monooxygenases (CYPs) are a heme-containing superfamily of enzymes that catalyze the activation of molecular oxygen to perform mixed-function oxidations. Relying on NAD(P)H for electron regeneration, these biocatalysts facilitate complex transformations - including C-hydroxylation, N-, O-, and S-dealkylation, and epoxidation - on diverse substrates such as xenobiotics, steroids, and fatty acids. Their ability to functionalize non-activated C-H bonds provides a precise alternative to traditional chemical oxidation, which often lacks the regioselectivity required for complex molecular scaffolds.