When listing three items in a series, what is the protocol on the Harvard comma? The mountain road was rigid, rocky and rolling. The mountain road was rigid, rocky, and rolling. In band, I played a song called "Hope, Honor and Glory". In band, I played a song called "Hope, Honor, and Glory". Is the Harvard comma the third comma you place in? Or is it the process of omitting the third comma, as it is deemed useless? Signed, clueless.