Most Sarcocystis spp. infestations are asymptomatic and the cysts in various muscles are only discovered at slaughter. Sheep of all ages may be affected by sarcocysts but neurological signs originating from spinal cord disease are believed to be the most common disease presentation and are reported in 6 to 12-month-old lambs. These clinical signs are easily mistaken for vertebral empyema, therefore the prevalence of neurological disease caused by Sarcocystis spp. in the UK is probably under estimated. Lesions involving the brain result in a range of clinical signs from reduced mentation to hyperexcitability and seizure activity. Cerebrospinal fluid (CSF) collection and analysis may prove the most useful ancillary test in establishing a likely diagnosis in practice, with an increased lumbar CSF white cell count and elevated eosinophil percentage being consistent with parasitic infestation.