  The Wisconsin H-Alpha Mapper (WHAM) has completed a velocity-resolved map of
diffuse H-alpha emission of the entire northern sky, providing the first
comprehensive picture of both the distribution and kinematics of diffuse
ionized gas in the Galaxy. WHAM continues to advance our understanding of the
physical conditions of the warm ionized medium through observations of other
optical emission lines throughout the Galactic disk and halo. We discuss some
highlights from the survey, including an optical window into the inner Galaxy
and the relationship between HI and HII in the diffuse ISM.
