xEuropean Union Member States increasingly draw attention to the choic
e between and within various decision rules. Two prominent approaches,
relative voting power studies and spatial models, assess the choice w
ithin the standard. cooperation, and co-decision procedures. However,
they cannot sufficiently explain the Member States' choice of these ru
les. In this article, we present our model on absolute inclusiveness a
nd relative decisiveness referring to two aspects of Member States' ch
oice: their absolute chances to be incorporated in collective decision
-making and their relative chances to be decisive actors thereby. We a
rgue that the combination of both power aspects gives insight into the
choice of rules, and we apply both indices to the actual power distri
butions in the Council of Members.