Single-celled eukaryotes called protists are vitally important to marine ecosystems. Protists with chloroplasts (algae) carry out most of the primary production in the sea. What feeds on this algal production? Mainly predatory protists such as ciliates in the microzooplankton, organisms that are 20 to 200 microns in size. This fact is well supported by empirical data. Still, predatory protists remain the Rodney Dangerfield “I don’t get no respect” of planktonic organisms. Compared to the amount of investigative effort devoted to bacteria, phytoplankton, and crustacean zooplankton, these protists, while unquestionably the dominant consumers of other microbial cells in plankton food webs, just don’t seem to get the research interest they deserve.