The present invention is related to antibodies directed to IL-13 and uses of such antibodies. For example, in accordance with the present invention, there are provided human monoclonal antibodies directed to IL-13. Isolated polynucleotide sequences encoding, and amino acid sequences comprising, heavy and light chain immunoglobulin molecules, particularly sequences corresponding to contiguous heavy and light chain sequences spanning the framework regions (FR's) and/or complementarity determining regions (CDR's), are provided. Additionally, methods of using these antibodies to treat patients are also provided. Additionally, IL-13 dependent biomarkers and methods of their identification and use are also provided.