Almost half of American families did not adjust their consumption following receipt of the 2001 or 2008 tax rebates. Another 20 percent, with low income and more likely to rent, spent a small but significant amount. Households with large spending propensity held high levels of mortgage debt. The heterogeneity is concentrated in a few nondurable categories and a handful of "new vehicle" purchases. The cumulated predictions of the heterogeneous response model tend to be smaller and more accurate than their homogeneous response model counterparts, offering new insights on the evaluation of the two fiscal stimulus programs. (JEL D12, D91, E21, E32, E62) "When a full analysis of heterogeneity in responses was made [in microeconometric investigations], a variety of candidate averages emerged to describe the 'average' person, and the long-standing edifice of the representative consumer was shown to lack empirical support." -James J. Heckman (2001, p. 674) "We may expect to see that integrating individual coefficients [from models of heterogeneous responses] yields roughly mean effect as estimated by the associated least-squares coefficient. One should be cautious, however, about this interpretation in very heterogeneous situations." -Roger Koenker (2005, p. 302) In the aftermath of the recent financial crisis, governments around the world have sought to support the economy through unprecedented fiscal interventions. Considerable uncertainty (and disagreement among economists) exists, however, around the impact of these policies. At the heart of this uncertainty lays the recognition that the effects of fiscal policies on the aggregate economy cannot be fully understood without explicit consideration of distributional dynamics. This important insight feeds into a growing macroeconomic literature which explicitly recognizes that consumers and entrepreneurs are inherently different in their access to