In this paper, we seek to quantify the importance of state-level housing price spillovers and interest rate shocks to house price developments in the United States. The econometric approach involves an application of the recently developed global VAR (GVAR) as presented in Dées, DiMauro, Pesaran, and Smith (2005) and Pesaran, Schuermann, and Weiner (2004) to the 31 biggest US states over the period 1986-2005. Such an approach allows not only for the empirical derivation of the impact of common shocks (such as interest rate shocks) on US house price developments, but also for an analysis of the importance of interstate housing price spillovers. Beyond real house prices and real income per capita, each state-specific vector error correction model also includes nation-wide variables — measured as a weighted average of other states —. These individual state models are then linked in a consistent and cohesive manner. Impact elasticities indicate strong interregional linkages for both real house prices and real income per capita. An analysis of generalised impulse responses indicates that the importance of housing price spillovers is state dependent, with shocks occurring in states with relatively lower land supply elasticities having much stronger spillover effects that those in the other states. As regards real interest rates, the impact appears to be relatively small with an increase of 100 basis points in the real 10-year government bond yield resulting in a long run fall in house prices of between 0.5 and 2.5%. This would suggest, in line with DelNegro and Otrok (2005) that the decline in long-term interest rates is not the primary factor that has driven the recent surge in house prices in the United States.