SCOR WG 134 on The Microbial Carbon Pump in the Ocean put together a supplement to the journal Science issued on May 13th and available in electronic form at  http://science.imirus.com/Mpowered/book/vscim11/i2/p1. T he supplement brings together past articles published in Science with new review papers. SCOR appreciates the efforts of the working group, under the leadership of the co-chairs Nianzhi Jiao and Farooq Azam, and contributions from several different co-sponsors, including Xiamen University, the U.S. National Science Foundation, national SCOR committees, and ASLO.