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Interlocal Cooperation

This page provides a basic overview of interlocal cooperation for local governments in Washington State, including examples of interlocal agreements.


Overview

Washington's Interlocal Cooperation Act, chapter 39.34 RCW, authorizes public agencies to contract with other public agencies via interlocal agreements that enable cooperation among the agencies to perform governmental activities and deliver public services. The Act also allows the creation of nonprofit corporations to carry out these ends.

Interlocal cooperation can reduce duplication, offer economies of scale, and generally improve governmental efficiency. Local governments engage in a wide array of cooperative efforts with each other, state agencies, and other governmental entities, and interlocal cooperation can take many forms.

All interlocal agreements made pursuant to Ch. 39.34 RCW must either be filed with the county auditor or posted on a public agency's website or other electronically retrievable public source (RCW 39.34.040).

While there is no penalty for failure to file or post agreements, a court of appeals decision, State v. Plaggemeier (1999), held that an agreement may be found invalid if it has not been filed or posted as required by RCW 39.34.040. Plaggemeier was decided under an earlier version of RCW 39.34.040 which required the filing of an interlocal agreement with the county auditor and secretary of state. That statute, however, has been twice amended and now only requires filing the agreement with the county auditor or listing it on the agency’s website. Even with the change in the statutory language, Plaggemeir is important as it indicates that an interlocal agreement could be invalidated by a court if it is not properly filed or listed.


Areas of Interlocal Cooperation and Sample Agreements

See the MRSC webpages listed below for sample agreements in specific subject areas.


Cooperation Policies

Some local governments have entered into agreements or adopted policies outlining their intent to pursue opportunities for joint coordination and action on issues of mutual interest with neighboring jurisdictions. See the following sample agreements and policies:


Recommended Resources


Last Modified: January 06, 2023