Harold Dull set up the Registry on which students could combine classes attended elsewhere with those they attended at his school at Harbin Hot Springs where he developed Watsu. A change in the California law made it impossible to continue the school's Watsu program unless it became a non-profit. WABA was set up as a California educational non-profit association which purchased the school from Harold. It's Board of Directors solicited volunteers from the Registry to help oversee the programs on the Registry in an Educational Standards Advisory Committee, and the ethics of those on the Registry in an Ethics Committee.

When the rent being charged for operating the school at Harbin forced the school to be sold again, WABA, which had been created to operate the school, reduced its operations to operating the committees and was eventually dissolved. By that time, instructors on the Registry had formed a new WABA to continue the services provided by those committees and develop additional ways to serve the public. This new WABA is a democratic member association based in Switzerland and anyone who wants to help is invited to become a supporting member