In this paper, we study the problem of large deviations for measures w
ith random weights. We are motivated by previous work dealing with the
special case occuring in the statistical mechanics of the Bose gas. W
e study the problem in an abstract setting, isolating what is general
from what is dependent on Bose statistics. We succeed in proving the l
arge deviation principle for a large class of measures with random wei
ghts and obtaining the corresponding rate function in an explicit form
. In particular, our results are applicable to the Fermi gas and the s
pherical model.