This is a report of a case of toxoplasmosis occurring in Holland in a 6-week-old infant, in whom during life Toxoplasma could be shown in the cerebrospinal fluid by smear and also isolated by mouse inoculation. The serum of the infant''s mother showed a strongly positive neutralization reaction, which was carried out by Sabin''s rabbit skin test. In cross-neutralization tests and cross-immunity expts. on rabbits, the Dutch strain appeared to be closely related to, perhaps identical with, an American one.