In his previous role as President, Newhall Land, McWilliams managed the entitlement, planning and development of Newhall Ranch and the final phases of Valencia.  Prior to joining Newhall Land, McWilliams was at Lennar, most recently as Regional President of Lennar Urban Communities in California and as President of Lennar Communities in the Bay Area, where he managed complex development projects involving the transfer of military bases.

McWilliams currently serves as Chairman of the California Business Properties Association in Sacramento and Chairman of the Global Land Use and Economic Council (for Southern California Association of Governments).  He also serves on the Executive Board and is former Chairman of the Southern California Leadership Council (SCLC).  He sits on the Board of Directors of the California Chamber of Commerce, the Building Industry Association, and the Santa Clarita Valley Economic Development Corporation.  He recently joined the Board of Trustees of the California Institute of Arts, Board Member of Los Angeles Area Chamber of Commerce, and Board Member of Coro Southern California.