The Case for Neutrino Oscillations

No abstract appeared in the Proceedings, but I am adding the following summary at the request of the X^3 people: The idea of neutrino masses is discussed in the context of grand unified theories., and various scenarios are presented, including the seesaw mechanism. At the end, preference is stated for maximal mixing between ${\nu }_{\mu }$ and ${\nu }_{\tau }$, and small mixing with ${\nu }_e$.