A version of this story originally appeared on PressDemocrat.com, also part of the Sonoma Media Investments news network.

St. Joseph Health has created a managed care network that brings together several local hospitals and more than 360 primary and specialty care physicians in Sonoma and Napa counties, the health care system announced Feb. 11.

The network, called the St. Joseph Health Medical Network, will launch April 1 and start a phased rollout as it begins transferring patients to the new network, which will be operated by St. Joseph Heritage Healthcare. Heritage is part of Providence St. Joseph Health, and is comprised of eight medical groups and six affiliated physician networks throughout the state.

Heritage late last year received approval from the California Department of Managed Health Care to form the new network, according to Bob Just, Northern California chief operating officer, St. Joseph Heritage Healthcare.

The just-formed network includes St. Joseph Health physician practices and clinics, along with Santa Rosa Memorial Hospital, Queen of the Valley Medical Center and Petaluma Valley Hospital. Patients using the network will have access to a full range of primary care doctors and specialists, hospitals, outpatient and urgent care centers, according to the announcement.

Previously, doctors in the fledgling St. Joseph Health Medical Group partnered with Sutter Health and the Meritage Medical Network to contract with large commercial HMO networks. The St. Joseph Health Medical Group has now grown large enough to form its own network and contract directly with HMOs, according to the announcement.

“We’ve reached the size where our medical group is large enough and our hospital services are broad enough,” Just said.

Further, he added, by forming its own managed care network, St. Joseph Health is better positioned to compete with entities like Kaiser Permanente.

SJHMN also will collaborate with the UCSF Medical Center and other academic health institutions for advanced and highly specialized levels of health care.

St. Joseph said the network is expected to contract with most major HMO and Medicare Advantage plans for seniors. For seniors, the network will deepen its affiliation with HMO Western Health Advantage and SCAN Health Plan.

The patients will receive a new health insurance card with “SJHMN” listed as their medical network, rather than, say, Meritage Medical Network. St. Joseph said the assigned physicians for this initial group of patients will not change.

North Bay Business Journal staff writer Cheryl Sarfaty contributed competitive context and history to this report.

A version of this story originally appeared on PressDemocrat.com, also part of the Sonoma Media Investments news network.