Diabetic retinopathy represents a serious health threat to a rapidly growing numberof patients with diabetes mellitus. The retinal microangiopathy is characterised byvascular lesions with exudate deposits and haemorrhages causing vision loss.Pycnogenol^®, a standardised extract of the bark of the French maritime pine (Pinus pinaster), is known to increase capillary resistance. Pycnogenol^® has been tested for treatment and prevention of retinopathy in five clinical trials with atotal number of 1289 patients since the late 1960''s. All but one of these studies have been reported in French and German and, today, are of limited accessibility, giving the impetus for reviewing them in detail in this article.There were two open case studies and two double blind studies (one controlledagainst calcium dobesilate and another against placebo) and, finally, one multi-centerfield study with 1169 diabetics. All of these studies unequivocally showed thatPycnogenol^® retains progression of retinopathy and partly recoversvisual acuity. Treatment efficacy of Pycnogenol^® was at least asgood as that of calcium dobesilate. Pycnogenol^® was shown toimprove capillary resistance and reduce leakages into the retina. Tolerance wasgenerally very good and side effects were rare, mostly referring to gastric discomfort.In conclusion, treatment with Pycnogenol^® had a favourable outcomein the majority of the patients with diabetic retinopathy.