A parallel extension of Sather for a clustered shared memory model. It features threads synchronised by monitor objects ("GATes") localityassertions and placement operators. There is an implementation for the CM-5. ["pSather Monitors: Design, Tutorial, Rationale and Implementation", J.A. Feldman et al, TR-91-031 and TR-93-028, ICSI, Berkeley, CA]. (1995-03-13)