The problem of efficient utilization of the radiofrequency spectrum is becoming more complex due to the increasing demands on the spectrum, which is a limited natural resource. If this natural resource is to be used efficiently, administrations need to use advanced Automated Spectrum Management Systems (ASMS) which would facilitate national spectrum management and monitoring, coordination among administrations and notification to International Telecommunication Union (ITU). This paper presents some of the spectrum engineering analysis and planning tools of the National Frequency Management System (NFMS) as part of the ASMS which has been developed for the administration of Turkey. This system includes a Relational Database Management System (RDBMS) to support a database containing frequency assignment data, licence holder data and equipment characteristics data. The software is integratedwith a Geographic Information System (GIS) and it has the capability of using digital terrain data and geographic data