  Continuous phase transitions are catalogued into universality classes,
families of systems having identical values of all the exponents governing the
critical behaviour of their different physical properties. Numerical
simulations have been carried out on Ising Spin Glasses in dimension three,
using a technique where corrections to finite size scaling can be controled.
The data show that the critical exponents vary strongly as a function of the
kurtosis of the interaction distribution, a parameter which from the standard
point of view should not be pertinent. This observation implies that for spin
glasses the renormalization group analysis should not be approached in a the
same way as in the case of canonical second order transitions; a much richer
structure of universality classes would appear to exist for spin glasses.
