Your brain mediates everything that you sense, feel, think, and do. The brain is incredibly complex - each cubic millimeter of your brain contains perhaps a hundred thousand cells, connected by a billion synapses, each operating with millisecond precision. We develop tools that enable the mapping of the molecules and wiring of the brain, the recording and control of its neural dynamics, and the repair of its dysfunction. We distribute our tools as freely as possible to the scientific community, and also apply them to the systematic analysis of brain computations, aiming to reveal the fundamental mechanisms of brain function, and yielding new, ground-truth therapeutic strategies for neurological and psychiatric disorders.