[en] This paper reports briefly on the symposium organized by the Plasma Research Center, University of Tsukuba, Ibaraki, Japan from 15 - 18 April 1980. The open plasma devices under investigation were devided into four general types: a) the electrostatic potential plugged mirrors; b) the radio-frequency (RF) - plugged mirrors and cusps; c) field-reversed mirrors and d) linear multiple mirrors