The Frequency Assignment Problem is an NP-complete problem which occurs during the design of a cellular telecommunication network. In this paper we describe a real-world frequency assignment scenario. We designed a Breeder Genetic Algorithm (BGA) capable of dealing with up to 5500 carriers which have to be assigned frequencies. The total number of available frequencies is about 50. The optimization goal is twofold: to assign as many frequencies as possible and to minimize the interference costs which are caused by the assignment.