Gasdynamic flow phenomena during the dwell time of exploding wires and their importance in reignition problems are investigated. Schlieren photographs show a shock wave inside the metal vapor cylinder converging to the axis. According to the theory of detonation this shock wave determines the radial distribution of temperature, pressure, and density in the vapor cylinder. It is shown, that reignition occurs always at the radius of minimum vapor density. Denoting the moment of reignition as tZ and the moment, when the converging shock wave reaches the axis, as tR, the following types of discharge may be distinguished: 1) For tZ < tR reignition occurs immediately in front of the inward facing shock wave. 2) For tZ > tR reignition starts in the axis of the vapor cylinder. © 1968, IEEE. All rights reserved.