Dignity Health, the fifth largest health system in the nation, announced today that it has signed a definitive agreement for the acquisition of Valencia-based U.S. HealthWorks, the country’s largest independent operator of occupational medicine and urgent care centers.

Terms of the deal, which is subject to certain regulatory approvals, were not immediately announced. The acquisition is expected to be finalized in August.

Dignity Health said the acquisition will help it extend its services to new care settings in order to deliver quality care more efficiently. The acquisition reflects organization’s vision to become a national, integrated delivery network by 2020.

U.S. HealthWorks, a portfolio company of Altaris Capital Partners and Three Arch Partners, operates 172 locations nationwide, and employs more than 2,700 employees, including approximately 800 medical providers. The company serves 12,000 patients a day.

“We are excited to bring U.S. HealthWorks into the Dignity Health family,” Lloyd H. Dean, president and chief executive officer of Dignity Health said in a prepared statement. “This allows us to expand our health care ministry into 16 states, and it strengthens our ability to deliver the integrated, quality care that people expect and deserve.”

Based in Valencia, Calif., U.S. HealthWorks offers occupational health care and urgent care services, preventive care, pre-employment and post-offer exams and screening, and return-to-work rehabilitative care. U.S. HealthWorks partners with more than 80,000 employers, many of them Fortune 100 companies, to help manage and reduce the cost of work-related injuries.

“We are very pleased to become part of a dynamic organization like Dignity Health,” Daniel D. Crowley, CEO of U.S. HealthWorks said in a prepared statement. “Dignity Health provides a great platform for us to continue growing our network to provide high-quality health care services throughout the country.” Mr. Crowley will continue on as the president and chief executive officer of U.S. HealthWorks, which will operate through a wholly-owned, for-profit subsidiary of Dignity Health focused on the occupational health care practice.

Dignity Health plans to expand the U.S. HealthWorks nationally. The San Francisco based health care system, which recently changed it name from Catholic Healtcare West, is also investing in ambulatory surgery and imaging centers through its partnerships with United Surgical Partners International (USPI) and SimonMed Imaging. Dignity Health currently has 17 joint-venture surgical centers with USPI, and 35 imaging centers with SimonMed.