We investigate the comovement among Case-Shiller Home Price Indices for 14 metropolitan areas between 1992 and 2008. We define the portion of this comovement deemed as fundamental (excessive) as the covariation that can (cannot) be attributed to common fundamental factors directly influencing real estate prices. We find that i) comovement among these markets considerably increased over the sample period, especially in the late 1990s; ii) this increase is mostly attributable to underlying systematic real and financial factors, consistent with a greater fundamental integration of those markets; and iii) excess comovement is a less important factor than commonly believed. We discuss the implications of these results for the evolution of U.S. real estate prices over the last two decades and the ongoing credit crisis.