As a free-admission public outdoor sculpture park with both permanent and visiting installations, it is a unique institution in the United States.

A $30 million gift from Mary and Jon Shirley (former COO of Microsoft and Chairman of the Seattle Art Museum Board of Directors) established them as foundational donors.

As part of constructing the sculpture park, 5.7 million dollars were spent transforming 1,000 feet (300 m) of the seawall and underwater shoreline inside Myrtle Edwards park. A three level underwater slope was built with 50,000 tonnes of riprap. The first level of the slope is large rocks to break up waves. The second is a flat "bench" level to recreate an intertidal zone. The lower level is covered with smaller rocks designed to attract sealife and large kelp. It is hoped that this recreated strand will help revitalise juvenile salmon from the Duwamish River and serve as a test for future efforts.

Maintenance of the sculptures has been an ongoing issue. The environment near a large salt water body has been corrosive to pieces like Bunyon's Chess, made primarily of exposed wood and metal. Tall painted pieces such as Eagle need to be watched for damage from birds and their waste. Maintenance of these large structures is expensive, requiring scaffolding or boom lifts. The paint on Eagle is also damaged by grass clippings near the base of its installation, requiring the gardeners to use scissors instead of a lawn mower near the sculpture.