This issue of theJournal of Geophysical Researchcontains seven papers that describe results from a cruise of R/VWecoma, which worked in the equatorial Pacific in February and March 1988. The name of the cruise was WEC88. The research plan for this cruise was based on the evolving understanding of the regulation of biological productivity in equatorial waters. When the eastern and central equatorial Pacific was originally found to be richer than waters to the north and south, the first question oceanographers asked was, “Why is the tropical region so rich?” Early work established that a zonal band straddling the equator and extending across the entire Pacific basin has enhanced nutrient concentrations, increased phytoplankton productivity, and increased abundance of Zooplankton and fish [Sette, 19