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Experiments on plasma confinement in stellarators started at the Max-Planck-Institute of Physics and Astrophysics immediately after the 1958 Geneva Conference and were continued at IPP Garching. The first devices of the Wendelstein line were W I-A and W I-B, both racetrack-type stellarators. In the circular = 2 stellarator W II-A, steady-state barium plasmas were investigated and were found to be governed by collisional diffusion. In W II-B, mainly Ohmic heating was applied. The main stellarator experiment at IPP Garching is W VII-A; after a period of Ohmic heating, the first net-current-free plasma was achieved in 1980. Plasma parameters of up to Ti= 1 keV and n(0) = 1014cm?3could be reached by this method. A further heating method is ECRH, which yields maximum electron temperatures of Te? 2 keV. The paper describes the major results of the devices mentioned and gives a short survey of further planning.

The Twelfth IAEA Conference on Plasma Physics and Controlled Nuclear Fusion Research featured some seventy tokamak experimental papers, pertaining to every issue of tokamak physics. While previous conferences have sometimes been dominated by a single result, for example achievement of high n? or T-values, such was not the case of the Nice meeting. Rather, this conference was characterized by a multitude of excellent scientific results on virtually all aspects of tokamak behaviour: confinement, operational limits such as density and beta MHD stability, heating, current drive and, to a lesser extent, impurity control. Taken together, these results lay a solid foundation for continued progress and future steps.

Substantial progress was made during the period 1981-1986 in plasma parameters, physics understanding, and improvement of the stellarator/heliotron concept. Recent advances include (1) substantial achievements in higher plasma parameters and currentless plasma operation, (2) new theoretical results with respect to higher beta limits, second stability region, effect of a helical axis, effect of electric fields on transport, and reduction of secondary currents; and (3) improvements to the reactor concept. The key issues have been further refined, and the short-term direction of the program is clear; a number of new facilities that were designed to resolve these issues are about to come into operation or are in the final design stages. This report summarizes these advances.