Bill currently serves on the board of the North Hawaii Community Hospital and the Grassroot Institute of Hawaii and is a trustee of the Anna Perry-Fiske Charitable Trust.  He has previously served on the boards of the North Hawaii Hospice and the Parker School Trust.  He also served on the advisory board for the West Hawaii Fund and as a member of the Hawaii Island Leadership Council of the Hawaii Community Foundation.

Bill began his law practice with the Honolulu firm then known as Torkildson, Katz, Jossem & Loden in 1977.  In 1983, he moved to the Big Island, opening a branch of the firm in Kailua-Kona. In 1995, Bill left the Torkildson firm, acquired their Kona office and continued his practice there.  In 2000, the firm moved its main office to its present location in Waimea (Kamuela). On July 1, 2013, the firm was reorganized and his long-time associate became a partner in the present firm. 

Mr. Hastings has participated in numerous seminars and programs on estate planning and gift & estate tax law for the Hawaii Institute of Continuing Legal Education, the National Business Institute, Professional Education Systems, the Hawaii Society of CPAs, and the American College of Life Underwriters, as well as for several business and professional groups.  Bill has also taught Estate Planning as an adjunct professor at the University of Hawaii's Richardson School of Law.