This Element argues for a novel approach to the sciences within Thomism, namely, science-engaged Thomism, which, aligned with the recent science-engaged theology movement, asks theological and metaphysical questions that require the input of the natural sciences. Recent developments within Thomism show a new approach to the natural sciences, and, thus, the proposal is to encourage more of this discourse by portraying the differences between contemporary and past Thomism. Still, even if it takes a novel approach, science-engaged Thomism relies on a tradition of thought that possesses a vast arsenal of metaphysical tools. Thus, after presenting this approach and a concise introduction to some basic notions of Thomistic metaphysics, the Element reviews some theological and philosophical questions and their relation to the natural sciences: issues about creation, cosmology, and astrobiology, divine involvement in evolutionary biology, providence and indeterministic quantum processes, and some ideas for further development at the end. This Element explores what Thomism has to offer to the contemporary debates on science and theology within Christianity.