When I was asked to organize this symposium on marine producti vity, it made me reflect on what aspects of this subject would be stimulating to a heterogeneous group of laboratory-oriented physiolo gists and biochemists. In recent years there have been several books which discusses the methodology commonly used in primary production studies and described the magnitude of photosynthetic CO reduction 2 in various areas of the world's oceans. I therefore decided to dis pense with these conventional aspects of primary production and invite researchers to speak on a variety of problems relating...