I am a chemist. I am passionate about chemistry because of its central and tremendously diverse role in the entire scientific enterprise. Chemists can be doctors, inventing drugs and materials for medical implants. Chemists can be architects, designing materials that can confer resilience, strength and aesthetic shapes to building materials. Chemists can be physicists, calculating structures of molecules using quantum mechanics and shining lasers on them to interrogate their properties. Chemists can be astronomers, literally studying star stuff. Chemists can be climate and energy scientists, studying the impact of climate change on the carbon cycle and developing new materials for solar capture. Chemists can be biologists, probing the fundamental basis of life and its origins. Chemists can be chefs and perfumers, concocting uncanny approximations of natural fragrances and flavors for haute cuisine. Chemists can even be fashion designers, developing novel textiles and colours for the latest season. And chemists can be engineers in a very fundamental sense, building molecules atom by atom.