4209 20190507102225.0 10.1007/978-3-319-42928-1 DOI BKSECT-2019-0013 Defraigne, Pascale GNSS Time and Frequency Transfer 2017 1327 Time and Navigation are intimately linked and rely on each other. GNSS positioning is based on the measurement of time intervals needed by the signal to travel from the satellites to the receiving station on the Earth or nearby. The precision of GNSS positioning is reached thanks to atomic frequency standards onboard the satellites and the possibility to determine their synchronization differences at the sub-nanosecond level. Time is thereby the core of GNSS. Inversely GNSS is widely used for accurate time and frequency dissemination, as well as for the comparison of distant clocks as needed for time and frequency metrology. All these aspects of using GNSS for time/frequency applications will be presented in this chapter. NO Springer Handbook of Global Navigation Satellite Systems Teunissen, Peter J.G., Montenbruck, Oliver 978-3-319-42928-1 1187-1206 pascale.defraigne@observatoire.be BOOKSECT