An overview of the life of Willem Vervoort (1917-2010), noted specialist in Copepoda and Hydrozoa, director of the National Museum of Natural History/Leiden 1972-1982 and extraordinary professor of systematic zoology/Leiden University 1973-1982, is given. Lists of new taxa in the Hydrozoa for the period 1998-2010, and a list of publications for the same period are included; the period 1917-1998 was covered by Van Bruggen (1998). Vervoort introduced (frequently with co-authors, particularly in the Hydrozoa) 70 taxa of Copepoda (i.e. 1 family, 1 subfamily, 11 genera, 57 species) and 199 of Hydrozoa (i.e. 1 family, 11 genera, 181 species, 3 subspecies, 1 variety and 2 nomina nova). The publications are analyzed and it appears that a stupendous amount of work has been generated, as regards the Hydrozoa particularly in the years after his official retirement (1982-2010). A total of 170 papers covers more than 9500 pp. (fig. 2).