The present paper presents an overview of the GNSS repeater based approach for indoor positioning. The latest theoretical and experimental results are presented in order to highlight the interesting features of the proposed method. The advantages of this method in terms of accuracy, cost, and simplicity of the infrastructure will be identified furthermore. Indoor positioning is a very important topic, mainly in terms of continuity of services. This leads to many theoretical and experimental works in this field using a large range of techniques, from purely GNSS approaches to networks of physical sensors or Wireless Local Area Telecommunication Networks. Among all these techniques, the GNSS based ones present the advantage of making better use of the satellite receiver, which is considered to be the "best" solution for outdoor applications (even with the current limitations in urban canyon environments). Thus, techniques like High Sensitivity GPS or Assisted GPS have been widely investigated within the satellite community: results are interesting but it does not seem to give a definitive answer to indoor positioning. Pseudolites and repeaters are now solutions that could help in a final system with good accuracy and a large coverage: studies are being carried out and show encouraging results for both approaches. This paper focuses on the repeater system, previously described in various papers [1], presenting its latest theoretical and experimental results. The paper is organized as follows. Section 2 outlines the theory of the GNSS repeater based approach. The multipath propagation simulations, performed in order to provide us with deployment rules for the repeaters, as well as a better understanding of the multipath effects on the positioning accuracy, are described in Section 3. New receiver architectures, developed in order to optimise the accuracy of the measurements of the phase jumps, are presented in Section 4. Finally, real deployments and real conditions positioning results will be presented and discussed in Section 5, before concluding