ESDU 88017 gives vapour pressure for 18 compounds. The data were obtained by a method described in ESDU 84021 involving a critical evaluation of experimental results in the literature, extrapolated by a reliable method into the low pressure region, and fitted by a Wagner equation applying over the full liquid range from the freezing to the critical point. The coefficients of the equation are given for each compound and three tables of vapour pressure are included: in SI units at 5 K intervals, in atmospheres at 5 degree C intervals, in lbf/sq in at 10 degree F intervals. For each compound the sources of the data are listed and a table is given of likely uncertainties in values predicted by the equation that should be allowed for in any critical situation.