The International Symposium on Nuclear Electronics was held in Paris in November 1963. The subject matter of the Symposium was confined mainly to detectors (including spark chambers), data processing and fast electronics, though other related subjects were also touched on. The report attempts to summarize the general trends and directions of progress indicated by the many papers presented and draws attention to some individual papers which seem to mark the present limits of what can be achieved or which suggest the direction of future progress.