Book excerpt: The Marquesas Islands (French Polynesia) are an isolated group of volcanic hot spot islands in the SE Pacific Ocean. Intensive botanical exploration of the Marquesas for the Vascular Flora of the Marquesas Islands and Flore de la Polyn?sie fran?aise projects has resulted in numerous new collections. The nine precursor papers in this issue include three new combinations and descriptions of 18 new species and one new variety of ferns and flowering plants, bringing the total number of new species described in conjunction with these projects to 62. Most of these new species are extremely rare and localized, and they have been assigned preliminary IUCN Red List ratings of Endangered or Critically Endangered. This clearly demonstrates that field work and biological inventories are essential to enhance our knowledge of insular biodiversity and provide critical information for conservation of organisms and habitats. The Vascular Flora of the Marquesas Islands is a collaborative project between the National Tropical Botanical Garden, Smithsonian Institution, and D?l?gation ? la Recherche (French Polynesia) under the direction of David H. Lorence and Warren L. Wagner.