Kaiser Permanente is an integrated healthcare organization consisting of three distinct entities: Kaiser Foundation Health Plan, Kaiser Foundation Hospitals, and separate autonomous medical groups. It provides service in nine geographical regions, each with its own administration and Permanente medical group. The national headquarters is in Oakland, California. Medical services in Oregon and Washington are provided by the Northwest Permanente medical group. The region is unusual in that it provides a dental program and has a medical services research center.

The organization had its beginnings in World War II Portland. Early in 1941, Henry Kaiser and his associates began building Liberty Ships for the British Admiralty, which was losing merchant vessels to Nazi U boats. They built shipyards in Richmond, California, and on the Willamette River near the St. Johns neighborhood in north Portland. After the bombing of Pearl Harbor on December 7, 1941, Kaiser constructed two more shipyards—one on Swan Island, formerly the site of Portland's municipal airport, and one on the north side of the Columbia River, a mile east of Vancouver, Washington. Thousands of workers and their families came to the Portland-Vancouver area to work in the yards.

Henry Kaiser and his son Edgar, who was in charge of the Portland-Vancouver shipyards, saw that the medical care for the workers and their families would be woefully inadequate if they had to depend on the available healthcare system. They got in touch with Sidney Garfield, a surgeon who had organized a prepaid, group-practice, medical-care program for Kaiser's workers at the recently completed Grand Coulee Dam. Garfield believed that healthcare funding could be provided through a nonprofit medical foundation. Henry Kaiser agreed.

In July 1942, the Henry J. Kaiser Company established the Permanente Foundation in California, and within months the Northern Permanente Foundation was serving Portland-Vancouver shipyard workers. "Permanente" is derived from Permanente Creek on Black Mountain near Cupertino, California. Henry Kaiser's first cement plant was adjacent to the creek.

As the shipyards began closing down during the last year of World War II, the termination of the health plan was imminent and a small number of physicians decided to offer a health plan to the community. The Permanente Foundation Health Plan thrived in California, but it initially faltered in the Oregon-Washington area. Dr. Ernest Saward led the organization through this difficult time.

In 1959, Bess Kaiser Hospital was completed in north Portland, and the Vancouver Northern Permanente Hospital closed. The result was a substantial growth in health plan membership. The name Kaiser replaced the name Permanente for the title of the health plan; the medical groups retained the Permanente name.

In the early 1950s, Henry Kaiser involved himself more in the healthcare organization and interfered with physician management. In 1955, the differences between Kaiser and the physicians developed into a crisis, which was solved by a codified agreement regarding responsibilities and finances. The agreement allowed a healthy growth of a system with successful partnerships between regional Health Plan managers and regional medical directors.

In 1969, Saward, who believed that his longstanding leadership was interfering with the development of new leaders, took a leave of absence. Surgeon Lewis Hughes became medical director in Oregon and partnered with Health Plan Manager Scott Fleming. One of their projects was the planning and construction of Kaiser Sunnyside Hospital in Clackamas. In 1976, pediatrician Marvin Goldberg from the Kaiser Southern California Region became medical director and was joined by Daniel Wagster as regional manager. Their activities included expansion to Salem and Longview, Washington.

Pediatrician Fred Nomura was elected medical director in 1986; Michael Katcher was regional manager. It was a time of financial stress as well as a nurses' strike, but their partnership functioned successfully. In 1992, Medical Director Allan Weiland and Regional Manager Barbara West began an era of many changes: an attempt to affiliate with Group Health Cooperative of Puget Sound, the institution of electronic medical records, the closure of Bess Kaiser Hospital, and the utilization of community hospitals.

In 2001, Cynthia Finter was named president and regional manager, and the partnership of the health plan with the Northwest Permanente medical group was tested by a restructuring of operations. Internist Andrew Lum from the Colorado Permanente medical group became the executive medical director of the Northwest medical group in 2005, replaced by Northwest Permanente otolaryngologist Sharon Higgins in 2007.

Andrew R. McCulloch, from Catholic Healthcare Partners and University of North Carolina Health System, was president of Kaiser Foundation Hospitals and Health Plan of the Northwest from 2006 to 2017; his tenure was marked by $1.1 billion in capital improvements and over a billion dollars invested in community benefits. Ruth Williams-Brinkley was named president of Northwest Kaiser Permanente Health Plan and Hospitals in 2017, and Internist Imelda Dacones became president and CEO of Northwest Permanente in 2015.

The Kaiser Sunnyside Medical Center in Clackamas, which is licensed for 233 beds, includes a cardiovascular surgery center as well as an inpatient mental health unit. A 47,000-square-foot facility houses a computerized regional laboratory on the outskirts of northeast Portland. The Westside Medical Center in Hillsboro, which is certified Leed Gold, has 126 private beds for medical and surgery patients.

Membership was 615,000 in 2018. There were 58 medical offices and other facilities and 1,261 physicians. Regions covered include Portland, Salem, and Eugene in Oregon and Vancouver and Longview-Kelso in Washington.