One of the field surgeons for the construction site of Roosevelt Dam, sensing an opportunity, rented out a private residence in what is now downtown Mesa and opened a hospital.

Temporary hospital operations were established in the LeSueur residence, a two-story structure which looked like a mix of Queen Anne and prairie architectural styles.

In the years after World War II, the Phoenix area, including Mesa, experienced dramatic growth, with the cotton fields giving way to suburban residential subdivisions as well as retail, manufacturing and warehouse facilities.

In December 1958, a new three-story, $700,000 north wing was dedicated for Southside District Hospital[4] (the building was later converted into a Maricopa County service facility and eventually renovated for use by Benedictine University for their downtown Mesa campus).

Banner Children's at Desert (formerly Cardon Children's Medical Center, so named after a $10 million donation from a prominent local family[11]), a 248-bed pediatric facility on the Banner Desert campus, opened as the most recent standalone expansion of the campus (a seven-story pediatric patient tower) in November 2009 at a cost of $356 million.

[14][15][10] Health services offered at Banner Desert and Banner Children's at Desert include: clinical laboratory, diagnostic imaging, emergency room, inpatient care to support the medical and surgical specialties and programs, lung testing, noninvasive heart tests, maternity care, gynecologic surgery and an Organ transplant center.