The procurement of defence equipment is expensive, irreversible and uncertain. Thus, there are risks for dysfunctional investements. By postponing un investment these risks can be reduced. The logic is that during this period new information, which reduces the risks, can be obtained. This project aims at developing a method to calculate the value of postponing an investment. As a first step in this direction the project has focussed on the procurement of combat vehicles. The technique of "net present value" has been used to calculate the benefit of postponing the procurement. However, the calculated benefit has to be modified by reduced defence capability, co-operative strategies, the demand and the number of producers.