In the fall of 2009, Oregon Solutions facilitated a process involving many potential stakeholders -- to build a framework for a multi-agency agreement. 

That process culminated on December 10, 2010, with the signing of a Gateway Green Declaration of Cooperation, in which twenty-two organizations and agencies stated explicitly what they will do to help make Gateway Green a reality. 

The group agreed that, once built, the City of Portland manage the park, but the project development will be governed by a Consortium Agreement between Portland Parks & Recreation and several key stakeholders -- a group to be called the Gateway Green Governing Group (4G).

In February 2012, a Memorandum of Understanding between Oregon Department of Transportation (ODOT) and Portland Parks & Recreation was signed, outling the terms and process to be completd in order to transfer ownership of the land to the City of Portland. 

The Declaration of Cooperation was updated in 2012, with forty organizations signing the new document, each making a specific commitment to what they would do to help create the new park.