J. D. Hair & Associates, Inc. is a consulting firm based in Tulsa, Oklahoma. Our objective is to focus creative engineering talent on projects involving the installation of buried utilities by horizontal directional drilling (HDD).Since its founding in 1987, JDH&A has consulted on more than one thousand HDD crossings in locations ranging from Alaska to Australia. Included among our clients, who have been located on every continent except Antarctica, are Fortune 500 energy companies, major international design and construction firms, local utilities, and HDD contractors.JDH&A's leadership position in the specialized field of HDD crossing design is demonstrated by its experience. We invite you to take a few moments to review the selected projects presented on our website. We think you will agree that our firm's HDD design capabilities are unparalleled in the HDD Industry.