Disclosed herein are methods and compositions for inactivating TCR genes, using engineered nucleases comprising at least one DNA binding domain and a cleavage domain or cleavage half-domain in conditions able to preserve cell viability. Polynucleotides encoding nucleases, vectors comprising polynucleotides encoding nucleases and cells comprising polynucleotides encoding nucleases and/or cells comprising nucleases are also provided. Disclosed herein are also methods and compositions for expressing a functional exogenous TCR in the absence of endogenous TCR expression in T lymphocytes, including lymphocytes with a central memory phenotype. Polynucleotides encoding exogenous TCR, vectors comprising polynucleotides encoding exogenous TCR and cells comprising polynucleotides encoding exogenous TCR and/or cells comprising exogenous TCR are also provided.