Our research falls under the broad umbrella of photo-induced chemistry and molecular photocatalysis. In this work, we follow chemical transformations proceeding on a wide range of timescales; from ultrafast charge- and energy- transport dynamics in molecules and aggregates, to diffusion-controlled reactions involving photo-generated species. We are especially interested in very early-time dynamics - where energy is transported to catalytically active sites, charge separation is enacted, and where the initial stages of bond breaking takes place. To study these processes, we rely on state-of-the-art techniques in ultrafast optical spectroscopy – supported by a wide range of well-established techniques from the optical spectroscopy toolbox.