  We present distance modulus and reddening determinations for 72 Galactic
globular clusters from the homogeneous photometric database of Piotto et al.
(2002), calibrated to the HST flight F439W and F555W bands. The distances have
been determined by comparison with theoretical absolute magnitudes of the ZAHB.
For low and intermediate metallicity clusters, we have estimated the apparent
Zero Age Horizontal Branch (ZAHB) magnitude from the RR Lyrae level. For metal
rich clusters, the ZAHB magnitude was obtained from the fainter envelope of the
red HB. Reddenings have been estimated by comparison of the HST
colour-magnitude diagrams (CMD) with ground CMDs of low reddening template
clusters. The homogeneity of both the photometric data and the adopted
methodological approach allowed us to obtain highly accurate relative cluster
distances and reddenings. Our results are also compared with recent
compilations in the literature.
