Experimental studies of neutrinos are notoriously challenging due to the feebleness of their interactions with matter, so it may seem counterintuitive to suggest these “little neutral ones” could have played a central role in the development of our universe to its current matter-dominated state. This talk will provide an overview of the interesting physics questions associated with neutrinos, and will give an outlook on the global program to build bigger and better detectors to uncover the answers to these questions.