Disclosed herein are methods and compositions for modulating activity of CXCR4 genes, for example using zinc finger transcription factors (ZF-TFs) or zinc finger nucleases (ZFNs) comprising a zinc finger protein and a cleavage domain or cleavage half-domain. Polynucleotides encoding ZF-TFs or ZFNs, vectors comprising polynucleotides encoding ZF-TFs or ZFNs and cells comprising polynucleotides encoding ZF-TFs or ZFNs and/or cells comprising ZF-TF or ZFNs are also provided.