  It is widely believed that hadronisation leads to 1/Q corrections to e+e-
event shapes. We show that there are further corrections, proportional to (ln
Q)^A/Q with A=4C_A/beta_0~=1.6, associated with hadron masses and whose
relative normalisations can be calculated from one observable to another. At
today's energies these extra corrections can be of the same order of magnitude
as `traditional' 1/Q corrections. They fall into two classes: universal and
non-universal. The latter can be eliminated by suitable redefinitions of the
observables.
