Robert (Rob) Thomas is the principal of Scientific Solutions, a consulting company that serves the training, application, marketing and writing needs of the trace ele¬ment user community. He has worked in the field of atomic and mass spectroscopy for more than 45 years, including 24 years for a manufacturer of atomic spectroscopic instrumentation. He has served on the American Chemical Society (ACS) Committee on Analytical Reagents (CAR) for the past 20 years as leader of the plasma spectrochemistry, heavy metals task force, where he has worked very closely with the United States Pharmacopeia (USP) to align ACS heavy metal testing procedures with pharmaceutical guidelines. Rob has written almost 100 technical publications, including a 15-part tutorial series on ICP-MS. He is also the editor and frequent contributor of the Atomic Perspectives column in Spectroscopy magazine. In addition, Rob has authored three textbooks on ICP-MS and in 2018 completed his fourth publication, entitled Measuring Elemental Impurities in Pharmaceuticals: A Practical Guide. He has spent the past two years researching and writing this new book, Measuring Heavy Metal Contaminants in Cannabis and Hemp. Rob has an advanced degree in analytical chemistry from the University of Wales, UK, and is also a Fellow of the Royal Society of Chemistry (FRSC) and a Chartered Chemist (CChem).