Photochemistry is an essential part of our daily lifes as illustrated by the production of Vitamin D in our skin or providing vision with our eyes. It is also an exciting discipline that plays a crucial role in, for instance, synthetic chemistry, polymer science, and biomedicine. This course deals with different concepts of light-driven chemical reactions, which are based on the interaction of molecules with light. The reactivity of various functional groups and their application in interesing areas of research are discussed. This course is independent of, but complementary to, the course Molecular Photophysics. While photophysics is focused on the physical properties and behavior of molecules and materials in response to light, photochemistry is focused on the chemical reactions that are initiated or controlled by light.