J. D. Hair & Associates is a consulting engineering firm whose mission is to provide its clients with value through the artful application of technology. We are the industry leader in the design of horizontally directionally drilled pipeline crossings and have been key members of design teams for some of the most significant and challenging pipeline projects ever completed. Our engineers are comfortable conducting surveys in the field, performing design in the office, monitoring construction at the jobsite, or presenting the results of a research project. We are based in Tulsa, Oklahoma, but work on projects throughout the world.