This report is part of a pre-project study to investigate the possible benefits and the road to implementation for GBAS operations at Stockholm Arlanda Airport. The report was created jointly by Swedavia, Indra Navia, LFV and Novair. The project members have extensive competence in the areas of airport operations, Air Traffic Control, flight operations, environmental issues, international legislation and national regulations as well as technical aspects of the GBAS system. The study describes how GBAS functions and how GBAS operations relate to current operations. It describes a number of different applications of GBAS that can be used to improve air traffic management. A number of similar efforts in Europe and the USA are described. It goes on to explain how GBAS operations can be approved and implemented on a generic level. A site where it is feasible to position a GBAS ground station at Stockholm Arlanda Airport has been identified and an implementation project to progress towards implementations has been examined. The study proposes that a GBAS installation be implemented at Stockholm Arlanda Airport in a stepwise manner in order to provide full GBAS operations at the airport which fully exploit the potential benefits identified in this report. The most promising GBAS benefits that can be expected for Stockholm Arlanda Airport are primarily those that can reduce noise in specific areas using curved approaches, variable approach angles and/or multiple runway aiming points. From an ATC perspective it is deemed feasible to commence GBAS validation flights during periods of low traffic intensity in the coming years. However, performing curved operation in combination with GBAS in higher traffic intensity, mixed with traffic using straight-in approaches will be challenging. Airline operators find that an implementation of GBAS approach procedures and even more advanced GBAS procedures at Stockholm Arlanda Airport can be considered feasible, valuable and necessary. They see that the limiting factor will be the aircraft equipage rate which is nevertheless assumed to increase if incentives are clearly visible. GBAS technology is still under development and the market is still to be considered as immature. However, through testing and studies in the framework of SESAR, GBAS technology has shown the capability to also provide a number of operational benefits which are well worth further investigation.