Ostwald solubility coefficients of 74 compounds in dry octan-1-ol at 298 K have been determined, and have been combined with literature values and additional values we have calculated from solubilities in dry octan-1-ol and vapour pressures to yield a total of 161 log L O c t O H values at 298 K. These L O c t O H values are identical to gas-to-dry octan-1-ol partition coefficients, often denoted as K O A . Application of the solvation equation of Abraham to 124 values as a training set yielded a correlation equation with n=124, S.D.=0.125, r 2 =0.9970 and F=7731. This equation was then used to predict 32 values of log L O c t O H as a test set, giving a standard deviation, S.D. of 0.131, an average absolute deviation of 0.085 and an average deviation of -0.009 log units. The solvation equation for the combined 156 log L O c t O H values waslogL O c t O H =-0.120-0.203R 2 +0.560π 2 H +3.560 α 2 H +0.702 β 2 H +0. 939logL 1 6 ,n=156,r 2 =0.9972,S.D.=0.125,F=10573,where, n is the number of data points (solutes), r the correlation coefficient, S.D. the standard deviation and F is the F-statistic. The independent variables are solute descriptors as follows: R 2 is an excess molar refraction, π 2 H the dipolarity/polarisability, α 2 H the overall or summation hydrogen-bond acidity, β 2 H the overall or summation hydrogen-bond basicity and L 1 6 is the Ostwald solubility coefficient on hexadecane at 298 K. The equation is consistent with similar equations for the solubility of gases and vapours into methanol, ethanol and propan-1-ol. It is suggested that the equation can be used to predict further values of log L O c t O H , for which the solute descriptors are known, to within 0.13 log units.