Mercy Hospital St. Louis and St. Anthony's Medical Center, also in St. Louis, finalized their affiliation agreement.
Under the agreement, St. Anthony's will become Mercy Hospital's fifth acute care facility in the St. Louis area.
Mercy officials will hold a series of community roundtable listening tours to better understand the needs of the area.
As part of the agreement, Mike McCurry, executive vice president and COO of Mercy St. Louis, will become president of St. Anthony's.
The financial details of the transaction were not disclosed.
The organizations began discussing a possible affiliation in February, which was met with concern and unease from local physicians.