The H → τ τ decay is an important decay mode of the Higgs as it allows to measure directly the Higgs coupling to fermions. This paper presents the measurement of the H → τ τ cross section performed with the Run 1 dataset (2011–2012) collected by the ATLAS experiment and describes future perspectives for the Run 2 of the LHC, with particular emphasis on the importance of theory
uncertainties for this channel. In addition a CP violation measurement in the Vector Boson Fusion production of the Higgs will be shown, that demonstrates how the H → τ τ channel allows to measure the Higgs CP properties as well
