This bachelor thesis deals with public contracts from point of view of central purchasing system for the public sector. The existence of central contracting authorities abroad is going to be examined after the presentation of current state of public procurement in the Czech Republic. After the comparison of particular systems of public procurement a model of the Central agency for the public sector in the Czech Republic is going to be chosen. The practical part is focused on the situation after founding the Central agency for the public sector, on a principle of efficiency, transparency, on possible savings after the implementation of this agency and on the content of its activities. In the end of this thesis opinions of parliamentary polit...