Background: Focal spasticity can be a major drawback in the rehabilitation of stroke patients. Previous studies suggest a beneficial effect for botulinum toxin A (BTX-A) for relief of spasticity. Objective: To evaluate the safety and efficacy of BTX-A in the treatment of spasticity in a homogeneous group of stroke patients. Methods: In this phase III open label trial 19 stroke patients stable for at least six months were enrolled (mean age 53.1 (SD 3.27) years; range 26-72). There were 16 males and 4 females. Assessments: Clinical (Ashworth spasticity rating scale, scores for joint mobility, pain and frequency of spasms, Frenchay arm test (FAT)) and subjective (semi-quantitative rating scale filled out by the patient). Only hand and finger flexors were injected. The maximum dosage was 150 U BOTOX® (25 U/muscle), the mean dosage was 92.1 ± 31.6 U BOTOX®. Results: Ashworth rating scale and joint mobility scores improved from a median value of 2 at baseline to a median value of 1 one month after treatment, FAT scores also improved from a median value of 0 at baseline to a median value of 1 one month after treatment (Kruskall-Wallis test p < 0.01). Two-thirds of the patients rated their functional improvement as none or mild. Conclusions: Our study confirmed that BTX-A has an anti-spastic effect but its functional impact needs further evaluation.