Yes! Several laws fully protect the confidentiality of mediations, including RCW 7.07. Everything that happens in the mediation process is confidential. Anything discussed in mediation is always confidential and the mediator may not be asked to testify about what occurred in mediation, and may not write a report to the court (other than to say if mediation has occurred or not).
Most agreements can be written in a way to protect the confidentiality. This can be helpful to keep your personal, financial, and health matters confidential since court documents are generally available to the public, creditors, employers, family members, and children.