Spasticity is a widespread, disabling form of muscle overactivity affecting patients with central nervous system damage resulting in upper motor neurone syndrome. There is a range of effective therapies for the treatment of spasticity (e.g. physical, anaesthetic, chemodenervation and neurolytic injections, systemic medication and surgery), but all therapies must be based on an individualized, multidisciplinary programme targeted to achieve patient goals. Appropriate therapy should be based on the extent and severity of spasticity, but spasticity and its consequences, regardless of presentation or cause, are commonly treated with systemic agents. This may be ill-advised as systemic treatment is associated with many undesirable effects. In particular, elderly patients with post-stroke spasticity are at risk from the central adverse effects of systemic medication (e.g. sedation and gait disturbance), which make them more susceptible to falling, with an associated increased risk of fracture. The rising costs of fracture care and its sequelae are fast becoming an international problem contributing to high healthcare expenditure. Botulinum toxin type-A (BoNT-A) treatment is highly effective for some of the more common forms of spasticity and muscle overactivity, and has a favourable profile when compared with systemic agents and other focal treatments. Therefore, the clinical benefits of BoNT-A treatment outweigh the apparent high costs of this intervention, showing it to be a cost-effective treatment.