The Natural History Museum of London (UK) provides this magnificent Website on sea urchins. Well-written and beautifully designed, the primary purpose of the site is "to provide a taxonomic resource for the scientific community in which the genera and higher taxa of echinoid can be simply and rapidly identified." Spectacular color images form the basis of the identification keys, highlighting the important distinguishing characteristics of each Family or Genus of sea urchin. In addition, an introduction and orphology section provide beginning users with useful background information, and an Index to taxa offers detailed information for a subset of taxa. For scientists or anyone else interested in learning more about these beautiful marine invertebrates, this site is an excellent window into their taxonomy.