Turkish government changed the high-school placement system for several concerns in 2018. The government as a designer designates and orders schools to each student in terms of location. Then students reveal their preference list over these designated schools. The government desires students to be assigned to as possible as the closest schools. However, students’ preference list is independent from the designation order. In this context, there is an incompatibility between the students’ preferences and the concern of the designer. The thesis will solve this sort of incompatibility. Two-Stage-Generalized-Priority-Mechanism proposed in the thesis finds the set of all possible designer-optimal matchings. At the second-stage, TSGPM yields the best designer-optimal matching in terms of the students’ preference list. At the last part of the thesis, strategic properties of the mechanism will be discusse
