The first measurement of the Z → ττ cross-section reconstructing hadronic and leptonic tau final states is presented. The data collected in 2010 with the CMS detector (CMS Collaboration, JINST 3 (2008) S08004) from p-p collisions at √s = 7TeV, corresponding to an integrated luminosity of about 36 pb−1, are used. The cross section has been measured to be in good agreement with the
next-to-next-to-leading order electroweak prediction. The production of Z bosons decaying into tau pairs serves as an important benchmark for tau reconstruction and constitutes a reference Standard Model process for searches at the LHC, like the Minimal Supersymmetric Standard Model H → ττ
