VSP Global has agreed to acquire San Antonio-based Visionworks, a majority-owned subsidiary of Highmark Inc.

Highmark acquired the business, then called Eye Care Centers of America, in 2006 for an undisclosed price.

With a footprint of more than 700 stores in nearly 40 states, Visionworks will be the single-largest VSP network investment in VSP's 65-year history.

VSP expects adding the sixth-largest optical chain in the U.S. to be highly complementary to its current business. “With expanded nationwide access, we’ll provide our clients and members with an option for a more substantial, consistent and sustainable retail experience, further enhanced by the professional care of VSP network doctors,” VSP CEO Michael Guyette said in a statement.

The transaction will close as soon as the necessary regulatory approvals are obtained.