This document summarises the main findings of the 2018 Council of Europe Annual Penal Statistics on Prison Populations, better known under the acronym SPACE I. The rates and percentages presented here correspond to the European median values computed on the basis of figures weighted by the population and the number of inmates in each country (see Methodology for further details). Forty-five (45) out of the 52 Prison Administrations in the 47 Council of Europe member states answered the SPACE I 2018 questionnaire, which corresponds to a participation rate of 87%.