We present a new variance reduction method for Asian options under a general model framework. The three special cases we consider are Lévy processes, Heston stochastic volatility, and regime switching models. The proposed method combines a very effective control variate with conditional Monte Carlo. While the control variate can be used for any model allowing the numerical computation of the multivariate characteristic function of the log-return vector, conditional Monte Carlo is based on the unified representation of the three models. Computational results confirm that the new method performs better than available control variate methods.