The present paper deals with the West Indian marine Haplosclerida incorporated in the collections of the Zoological Museum of Amsterdam. A total of 36 species is described and fully illustrated. Part of the material consists of the Duchassaing & Michelotti collection housed in Amsterdam; of all the Haplosclerid types of this collection an extensive redescription and a photographic illustration is given. Most of the type specimens are designated (para-)lectotypes. Eight new species are erected, viz. Reniera curaçaoensis, R. carmabi, Sigmadocia piscaderaensis, Niphates alba, Xestospongia wiedenmayeri, X. portoricensis, Petrosia weinbergi, and Strongylophora hartmani. The follwing new combinations are used: Niphates amorpha (for N. digitalis forma amorpha Wiedenmayer, 1977), Cribrochalina spiculosa (for Siphonochalina spiculosa Dendy, 1887), Pellina nodosa (for Phloeodictyon nodosum George & Wilson, 1919), and Pachypellina podatypa (for Haliclona podatypa De Laubenfels, 1934). Several new combinations are suggested for species not represented in the present collection, but studied for comparative reasons. A new classification of marine Haplosclerid families is proposed, based on the study of the present collection, and on the study of many type species of Haplosclerid genera. The new classification comprises five families, viz. Haliclonidae, Niphatidae (n.), Callyspongiidae, Petrosiidae (n.) and Oceanapiidae (n.). The proposed classification is discussed and some phylogenetic ideas are presented. The zoogeography of the West Indian sponges is studied and some ecological data are given.