The changing symptomatology manifested by four normal young subjects throughout exposure to rotation in a Slow Rotation Room (SRR) was used in studying susceptibility to SRR sickness and transfer effects. A comparison was made between the effects of rotation in the SRR with man parallel (vertical mode) and those when he was at right angles (horizontal mode) to the axis of rotation, the situation in a rotating spacecraft. Attention was focused on motion sickness, ataxia, and the phenomenon of transfer of habituation. Susceptibility to motion sickness was similar in the two orientational modes. With the limitations of the experiment, the findings regarding SRR sickness indicate that habituation acquired in the SRR in one mode transfers to the other mode. The postrotatory perseveration of postural habituation to the rotating environment long after cessation of rotation shed some light on the underlying homeostatic mechanism involved. (Author).