A 5 month old castrated male mixed breed ram lamb was presented to the Ambulatory Service in September 2009 for evaluation of neurologic signs. The lamb demonstrated posterior paresis and decreased proprioception, especially in the left hind limb. He was in thin body condition (BCS 2.5/5) and had pale pink conjunctiva. The patient’s central nervous system lesion was localized to the T3-L3 region, based on full neurologic exam, and treatment for presumptive infection with Parelaphostrongylus tenuis migration was initiated. Concurrent parasitism with Haemonchus contortus was presumed and dewormers were administered. A fecal sample was taken for further evaluation of the herd parasite load; this revealed many strongyles (including few Nematodirus), Strongyloides and coccidia, and moderate levels of tapeworms. The treatment plan for this patient included oral amprolium and fenbendazole for 5 days, a tapering 5 day course of injectable dexamethasone, and one dose of oral moxidectin. The producer was given continuing education materials and advised on routine herd health procedures including rotational grazing, deworming strategies, and vaccination. General principles of the pathogenesis, diagnosis, and treatment of Parelaphostrongylus tenuis are discussed with emphasis on the small ruminant patient and new research in this field.