Acute thrombosis of the basilar artery has a fatal outcome if left untreated. The relatively good prognosis with intra-arterial thrombolysis makes it the therapy of choice for acute basilar thrombosis. In the Saarland stroke registry, we analyzed 47 patients with angiographically proven basilar artery thrombosis within the last 5 years. We observed a better outcome in patients with good income, with recanalization, and a short time between onset of symptoms and start of thrombolysis. The complications, such as intracerebral bleedings, occurred only in the group treated with rt-PA. Intra-arterial thrombolysis with urokinase or rt-PA is a relatively safe therapy, but should be performed in neuroradiological centers. With progressing symptoms the therapeutic window can be stretched up to 12 h, but coma lasting for more than 4 h is related to a bad outcome.