Although the perceptual phenomena of consonance and dissonance in music have attracted interest across a wide variety of disciplines for two and a half millennia, theoretical progress to date has been very limited. With guidance from musicians at CIM, CWRU, and elsewhere, and in collaboration with Brooke Macnamara in CWRU’s department of psychological sciences, I have launched a new theoretical effort in the area. In my talk, I will review the fascinating history of the problem, discuss our first results, and outline plans for the future.