Karl B. Scheidweiler earned his Ph.D. in Pathology from the University of Rochester in 2002 after completing his research dissertation on “Pharmacokinetics and actions of methylecgonidine, a component of crack cocaine smoke.” He worked as a Post-doctoral Fellow for Marilyn A. Huestis, Ph.D. at the National Institute on Drug Abuse, National Institutes of Health (NIDA-NIH) from 2002-2006 and served as a Staff Scientist at NIDA-NIH until 2016. During his tenure at NIDA-NIH, Dr. Scheidweiler developed and validated gas chromatography-mass spectrometry and liquid chromatography tandem mass spectrometry (LC-MS/MS) methods for numerous drug classes in various matrices, including oral fluid, to support Intramural Research Board (IRB)-approved controlled drug administration clinical pharmacokinetic/pharmacodynamic research studies. These clinical research studies provided data to assist interpretation of workplace, drug treatment and driving under the influence of drugs (DUID) cases. Dr. Scheidweiler served as an R&D Scientist from 2016-2020 developing LC-MS/MS methods for Prescription Drug Monitoring Toxicology laboratories at Quest Diagnostics. Since 2020, Dr. Scheidweiler has worked for Abbott (Immunalysis) in a Chief Toxicologist/Scientific Affairs role supporting development of various Toxicology products including urine and oral fluid screening immunoassays.