In ruminant species, cerebrospinal fluid (CSF) collection and analysis provide rapid (in some situations, instant) information to the veterinary clinician investigating a disease problem in the living animal. CSF analysis is particularly useful with respect to confirming the presence of an inflammatory lesion involving the leptomeninges,such as bacterial meningoencephalitis, and in investigating potential compressive lesions of the spinal cord. When correctly performed under local anesthesia, lumbar CSF collection in ruminants is a safe procedure and there are no harmful sequelae. Familiarity with the technique aids high extradural injection of lidocaine or xylazine, which has many applications in farm practice. There are few indications for cisternal CSF collection in food animals.