This paper describes an experiment carried out to assess whether ewes exposed to hairy shaker disease in their previous pregnancy by contact with artificially infected ewes (Lewis et al 1970) had acquired an immunity to the disease. The presence of immunity would indicate that the ewes had been infected during their period of contact, although only one ewe out of 28 produced an affected lamb. This would support the suggestion of Lewis et al (1970) that infection by contact may have occurred too late in pregnancy to produce affected lambs. Immunity, if it could be brought about in this way, would be of value in control of the disease. By recording mating data more fully than in previous experiments, it was hoped to obtain more precise information on the time of foetal death in cases where abortions occurred, and on the gestation period of the small hairy lambs which are characteristic of the disease.