Two or more parties may agree in writing to submit to arbitration.
RCW 7.04.010
Arbitration Contract
A written Arbitration Contract confirms the agreement of the parties to proceed with arbitration in accordance with their agreed terms and the requirements of RCW 7.04.010.
"Now, who shall arbitrate? Ten men love what I hate, shun what I follow, slight what I receive; ten who in ears and eyes match me: we all surmise, they this thing, and I that: whom shall my soul believe?"