Assumptions are a necessary evil in the working world. To move forward on decisions we often need assumptions in project planning, business cases, specifying requirements, estimations of any kind and surely many other cases. We assume in order to confront uncertainty. But, confrontation is not management. The old joke reminds us of the danger: “to assume” means to make an “ass out you and me”. Fortunately, there’s a better way: work with hypotheses instead.