Most current remediation practices generally fail (or are cost prohibitive) to remove the polycyclic aromatic hydrocarbons (PAHs) found in petroleum contaminated sites or they require organic solvents to effect removal, at the expense of additional contamination and with the added cost of recycling solvents. Hydrothermal extraction offers the promise of efficiently extracting PAHs and other kinds of organics from contaminated soils at moderate temperatures and pressures, using only water. In cases, where the pollution is severe (e.g., pollutant exists in a separate phase), equilibrium solubility determines the maximum attainable concentration, while the rate of solubilization determines the removal rate of pollutants from the matrix. Therefore, the rate of solubilization is a critical parameter that determines the efficiency and the cost effectiveness of the process. This paper presents the measured equilibrium solubility and the rate of solubilization data for selected PAHs (dimethylanthracene, fluoranthene, pyrene, and chrysene) in water using SRI's hydrothermal optical cell at 125°-200°C. No literature data are available on in situ measurements of solubilities of PAHs, and to our knowledge this is the first recording of solubility data for PAHs measured under hydrothermal conditions by in situ measurements.