The highly variable clinical course of cervical artery dissections still poses a major challenge to the treating physician. This study was conducted (1) to describe the differences in clinical and angiographic presentation of patients with carotid and vertebral artery dissections (CAD, VAD), (2) to define the circumstances that are related to bilateral arterial dissections, and (3) to determine factors that predict a poor outcome. Retrospectively and by standardised interview, we studied 126 patients with cervical artery dissections. Preceding traumata, vascular risk factors, presenting local and ischemic symptoms, and patientoutcome were evaluated. Patients with CAD presented more often with a partial Horners syndrome and had a higher prevalence of fibromuscular dysplasia than patients with VAD. Patients with VAD complained more often of neck pain, more frequently reported a preceding chiropractic manipulation and had a higher incidence of bilateral dissections than patients with CAD. Bilateral VAD was significantly related to a preceding chiropractic manipulation. Multivariate analysis showed that the variables stroke and arterial occlusion were the only independent factors associated with a poor outcome. This study emphasises the potential dangers of chiropractic manipulation of the cervical spine. Probably owing to the systematic use of forceful neck-rotation to both sides, this treatment was significantly associated with bilateral VAD. Patients with dissection-related cervical artery occlusion had a significantly increased risk of suffering a disabling stroke.