Melvin Stern was a brilliant theoretician who introduced a number of innovative ideas in oceanography. These include his (a) penetrating introduction of double diffusive processes, (b) introduction of MODONS, the important, small scale, coherent features in the ocean, (c) incisive studies of rotating hydraulics, (d) investigation into bores, jumps and boundary flows, (e) analyses of the role of vortices in ocean dynamics, and (f) frequent contributions to instabilities in the ocean. He tended to think very intuitively, not unlike Henry Stommel. When he introduced a new idea, he accompanied it with a very thorough analysis. Generally speaking, he communicated most effectively in one-on-one situations, particularly with his graduate students. In these situations he was a wonderful and positive critic. His ideas, particularly his work on salt fingers, permeated the field and led to extensive developments of topics that today are fundamental elements on which our understanding of oceanic processes is built.