International directory enquiries http://eporner.in.net/ hqporners Tenet set up a commercial accountable care organization in Modesto, California, in January 2012 after Kaiser Permanente, known for providing the ACO blueprint, built a medical center there. Tenet is now more deeply involved through its purchase, of a smaller hospital group, Vanguard Health Systems, finalized on October 1 for about $1.8 billion.