Most of the existing literature deals with consumer willingness to pay for GM-free food, or consumer willingness to accept for GM food. However, it is well know that consumers have mixed views about GM foods. In this research, we do not presume that all consumers may just have positive or negative preferences about GM products. Rather, heterogeneous preferences are considered. This paper presents a contingent valuation questioning sequence and associated modeling approaches that allow identification of both positive and negative preferences. Willingness to pay (WTP) for the GM product is contrasted with willingness to accept (WTA) compensation to buy it.