Theoretical Calculation of the Liquid-Vapor Coexistence Curve of Water, Chloroform and Methanol with the Cavity-Biased Monte Carlo Method in the Gibbs Ensemble Abstract: The Gibbs ensemble computer simulation method of Panagiotopoulos is combined by the cavity-biased sampling technique used previously in the grand-canonical ensemble. The combined technique is applied to the determination of the liquid-vapor coexistence curve of the Lennard Jones fluid as a test case, two water models (SPC and TIP4P) as well as methanol and chloroform, both described with the OPLS model. The application of the virial-biased sampling technique, used earlier in the isobaric ensemble is also discussed.