Preliminary List of the Compositae in Northeastern Brazil is the fourth title to be published in this series. Many specimens from this plant family were deposited at the Royal Botanic Gardens, Kew for historical reasons, and others have been added to the collections more recently as a result of the longstanding collaboration between Brazil and Kew. Between 2000 and 2001, 4200 Northeastern Brazilian Compositae specimens were examined, resulting in a checklist of 486 species in 143 genera, with entries listed alphabetically and sorted by state, collector and number. An additional exsiccatae list enables duplicates lodged in other herbaria to be checked against the correct determination. The database that underpins this checklist is available on the internet at: www.kew.org/scihort/tropamerica/repatriation.htm, along with images of the NE Brazilian type specimens held at Kew. Hard copies of such images are available at four Brazilian herbaria (CEPEC, HUEFS, IPA and HRB). They can also be viewed at Kew's general catalogue of herbarium specimens at www.kew.org/herbcat/navigator.do