Because of the similarities in European and North American dietary exposure, it has been suggested that the order of magnitude higher body burdens in North Americans may be due to international variations in exposure via ingestion of indoor dust. Furthermore, ingestion of indoor dust has been suggested as a possible source of PBDEs in the blood serum of New Zealanders. Hence, polybrominated diphenyl ethers (PBDEs) were measured in domestic indoor dust from: Amarillo/Austin, Texas, US; Birmingham, UK; Toronto, Canada; and Wellington, New Zealand. Concentrations of BDE 209 in two UK samples were - at 520,000 and 100,000 ng g(-1) - the highest ever recorded in a domestic (or office) indoor dust sample. Median concentrations in ng g(-1) were: in Canada 620 and 560 for Sigmatri-hexa-BDEs and BDE 209 respectively; in New Zealand 96, BDE 209 not determined; in the UK 59 and 2,800; and in the US 1600 and 1300. With respect to BDE 209, concentrations were in the order: UK approximately US>Canada. For Sigmatri-hexa-BDEs, the order of concentrations was US approximately Canada>>New Zealand approximately UK. Combined with principal component analysis of congener patterns, this suggests that, while North American dusts are contaminated by both Deca- and Penta-BDE commercial formulations, UK dusts are contaminated predominantly by Deca-BDE. The Octa-BDE formulation appears of minimal importance in accordance with available market demand figures. Despite the commercial formulations of PBDEs never having been manufactured in, nor imported into New Zealand, their presence in dusts from that country suggests international trade in PBDE-containing goods is an important pathway effecting their global distribution.