What isMeritage Medical Network. When you ask people who they want to be making decisions about their healthcare, most will answer: Doctors. At Meritage, doctors are the ones making the decisions about your healthcare. Meritage is a network of over 700 local physicians providing care for patients in Marin, Sonoma, Napa, and Solano Counties.Resources For Physicians‧Contact Us‧About Us‧Enrollment‧Announcements.