Throughout a long and accomplished career in neutron science, John J. Rush has been a leader, tirelessly promoting both the field itself and his home facility, the NIST Center for Neutron Research. Working with his close friend and colleague, Mike Rowe, he succeeded in expanding neutron scattering research at NIST from a small in-house effort to one of the world�s leading programs, serving a national and international user community. He has actively encouraged the application of neutron methods to many new areas, from biological science to the understanding of cement used in the construction industry. His own research on the dynamics of molecular solids and hydrogen in metals is widely recognized, with over 4000 citations to his 220+ publications.