  We present the explicit expressions for the resummation of large-x Sudakov
effects in the transverse-energy distribution of prompt-photons produced in
hadronic collisions, to next-to-leading logarithmic (NLL) accuracy.
Fragmentation processes do not contribute to the Sudakov resummation at NLL
level. In Mellin space, the resummed radiative factor factorizes in the product
of independent radiators for the two initial and the one final coloured partons
appearing in the Born process, times a simple factor describing the soft-gluon
interferences between initial and final states. The formulae are given in terms
of Mellin moments, and can be used for phenomenological applications using
standard techniques for the inverse-Mellin transforms. The calculations
presented in this work, when added to the existing works on DY and DIS
production, complete the theoretical ground-work necessary to carry out global
fits of parton densities with a uniform NLL accuracy in the large-x region.
