This paper considers a real options model with incomplete information in a duopoly setting. I show that even in the presence of a first-mover advantage, there are circumstances in which the preemption region is eroded entirely and the only equilibrium strategy is of simultaneous-type: both players should exercise together or not at all. This outcome arises if the price paid by a player from exercising the option simultaneously with his competitor (over exercising alone as a Stackelberg leader) is low. Such an outcome has not been previously recognised in the literature. The underlying information structure has been applied in a one-firm setting to a range of different contexts of late, all of which have competitive pressures in practice. As...