The morphological and haemodynamic findings in the vessels of the forearm and hand in 21 patients with progressive scleroderma are described. In these patients, brachial arteriograms have been carried out before instituting fibrinolytic therapy. Injections were carried out before and after intra-arterial Priscolin and the results were compared. Obliterative changes in the digital arteries are already present during the oedematous stage. Between the oedematous and advanced stages, there are vascular changes of progressive severity. In the sclerotic stage, the changes may be less marked, but more often consist of advanced obliterative vascular disease; this cannot be distinguished from the atrophic stage. The haemodynamics of the digital arteries can be influenced by Priscolin and this provides some information regarding the arterial side of the dermal micro-circulation. Even during the oedematous stage one can observe contrast stasis which is irreversible and not influenced by Priscolin.