And that's the problem with rankings. Because it matters what you mean by "top tier". I'd argue that Harvard CS is top tier, it's just much, much smaller than

And that's the problem with rankings. Because it matters what you mean by "top tier". I'd argue that Harvard CS is top tier, it's just much, much smaller than the schools it competes against. Michael Mitzenmacher, Leslie Valiant, Michael Rabin, Greg Morrisett, Eddie Kohler, Krzysztof Gajos, Margo Seltzer, and Barbara Grosz are all among the very best in their fields (or in the case of Grosz, were the very best before they went on to be Dean). In general the faculty are very, very high quality, but in contrast to a school like MIT or Washington, which have probably 60-80 of faculty, Harvard has only about 30.