  We identify a link between the glass transition and percolation of mobile
regions in configuration space. We find that many hallmarks of glassy dynamics,
for example stretched-exponential response functions and a diverging structural
relaxation time, are consequences of the critical properties of mean-field
percolation. Specific predictions of the percolation model include the range of
possible stretching exponents $1/3 \leq \beta \leq 1$ and the functional
dependence of the structural relaxation time $\tau_\alpha$ and exponent $\beta$
on temperature, density, and wave number.
