Inclusive Searches for Supersymmetry with Leptons with the ATLAS Detector

We report on preparations for inclusive searches for new physics, in particular supersymmetry, in events with one or two isolated high momentum leptons, and possibly jets and missing transverse energy, with the ATLAS detector at the LHC. We focus on the relevant performance of the ATLAS detector, in particular for the measurement of leptons, in first collision data. We study how Standard Model backgrounds to new physics can be extracted from the data, and we take a first look at the 7 TeV data set. We investigate the sensitivity of ATLAS for supersymmetry searches in this channel for the 2010-2011 LHC run.