This work presents a comparison of vapor-liquid equilibria (VLE) data and diffusion coefficients of the system poly(dimethylsiloxane) + n-pentane measured using three experimental methods: gravimetric sorption, pressure decay and inverse gas chromatography. These methods differ in the underlying experimental principles as well as in the complexity of data analysis. Despite of these differences, the agreement of the measured VLE data is excellent. Diffusion coefficients were measured with satisfactory accuracy using the gravimetric sorption as well as the pressure decay method. The VLE data are modeled using the PC-SAFT equation of state. (c) 2005 Elsevier B.V. All rights reserved.