IRD mass accumulation rate (MAR) records are presented for Deep Sea Drilling Project site 580 and Ocean Drilling Program sites 882 and 887 and are combined with results from previous IRD MAR studies to provide a synthesis of North Pacific Pleistocene ice rafting. Important regional differences in the ice rafting histories of the NW and NE Pacific are highlighted by this synthesis and include (1) significant variations in IRD fluxes across the North Pacific, which identify two major IRD sources, coastal Alaska and coastal Siberia/Kamchatka Peninsula, and (2) significant variations in the timing of IRD supply across the North Pacific, particularly in response to global-scale climatic forcing. These regional differences indicate that local and regional controls on iceberg input, transport, and melting exert a major influence on ice rafting throughout the North Pacific. This suggests that a single generalized ice rafting record for the North Pacific does not adequately describe the complexity of this basin's Pleistocene history. ¿ 1999 American Geophysical Union