Analytical data for North Sea oils and gas condensates have been measured. The data include GC and TBP analyses and measurements of molecular weights, specific gravities, and PNA-distributions of most TBP-fractions. For each mixture, a few dew and bubble points have been measured, and in addition PVT-data and separator flash compositions have been determined. These experimental results are simulated using the SRK equation of state and a suitable characterization procedure based on the analytical information. It is shown that accurate predictions of the phase behavior can be achieved using only a total of six hydrocarbon fractions. No “matching” or “tuning” to experimental phase equilibrium or PVT data is needed.