A perturbative QCD approach to the production of `naked' heavy flavour states in pp and bar pp interactions is outlined. The subprocesses considered are: qbar q → cbar c and gg → cbar c (flavour creation), qc → qc and gc → gc (flavour excitation). Calculated cross sections are presented, and discussed in the light of present experimental results for the hadronic production of charm. Although their calculation has substantial uncertainties, the flavour excitation processes, contrary to intuitive expectation, may be the dominant mechanism.