NTS was begun in 1995 by Howard Taylor, PhD who decided that drug testing is very personal and therefore requires personalized attention. To that end, he recruited two highly respected professionals to round out the management team. Together, we have the expertise to manage any aspect of drug free workplace management.


Howard Taylor, PhD is a nationally known board certified toxicologist with over 27 years experience in drug testing. He is board certified by the American Board of Forensic Toxicology ( ABFT ) and the American Board of Clinical Chemistry (ABCC) with a subspecialty in toxicology. Dr. Taylor is a SAMHSA (formerly NIDA) laboratory inspector. He has published 30 peer-reviewed articles, 13 book chapters and 2 books throughout his career. His animated trainings and expert witness testimony are in much demand all over the country.

Greg Elam, M.D. is certified by the American Association of Medical Review Officers. He has clinical experience in dealing with controlled substance disorders and has supervised the review of over two million drug tests. He brings a very professional and personable approach to the review of drug tests. The first interaction with someone knowledgeable about substance abuse disorders is likely with the MRO. Therefore, the MRO interview sets the tone for future interactions, giving the MRO the opportunity to provide a positive approach to a shame based condition. Dr. Elam epitomizes the professional but compassionate physician in dealing with drug test issues.

Tim Shoaf, MBA, MT(ASCP) received his MBA from Vanderbilt University and has 25 years experience in drug testing and toxicology. Most recently, he served as Director of Operations for a SAMHSA certified forensic drug testing laboratory. Mr. Shoaf’s knowledge of business and toxicology makes him unique in the drug testing world. With his contributions, NTS has all the expertise under one roof so clients can literally call one number for all their drug testing needs!