The issue of donor behavior and crowding out has been pertinent in the economics literature, both theoretically and empirically. Aggregate research has not been decisive, nor have many studies analyzed education institutions. I begin with a theoretical model of crowding-out versus crowding-in donor behavior. I then employ a fixed effects econometric model to three samples--total universities, public universities, and private universities. By implementing a longer time period and larger sample than previously seen in the literature, I can examine the crowd-out versus crowd-in effect of nonalumni private donations on alumni donations in the 12-year period from 1995 to 2006. The results demonstrate a statistically significant crowding-in effect--the charitable behavior of parents, corporations, and foundations positively influences alumni donating behavior. The reason may be that these nonalumni private donations serve as a signal of increasing school quality.