Chiral centers, also known as stereocenters, are atoms within a molecule that have four different substituents attached to them, leading to non-superimposable mirror images called enantiomers. These chiral centers are crucial in determining the optical activity and stereochemistry of a molecule. In the context of catalysis, the presence of chiral centers can significantly impact the outcome of catalytic reactions, particularly in the synthesis of pharmaceuticals and other biologically active compounds.