Edited by Kathleen P. Freeman, DVM, BS, MS, PhD, DipECVCP, FRCPath, MRCVS, RCVS, is an American-trained veterinary clinical pathologist who works in the UK as a senior veterinary clinical pathologist for IDEXX Laboratories. Dr. Freeman is also a consultant for the Veterinary Information Network and a founding Diplomate of the European College of Veterinary Clinical Pathology (ECVCP). She has been the founding chair for the Quality Assurance and Laboratory Standards Committee of the American Society of Veterinary Clinical Pathology (ASVCP) and for the Laboratory Standards Committee of the ECVCP. Dr. Freeman received the ASVCP Educator Award in 2014. She has special interests in quality assurance and quality control, biological variation, cytology and equine pathology. Stefanie Klenner, Dr.med.vet, DipECVCP, is a veterinary clinical pathologist located in Germany working as scientific product manager laboratory diagnostics for the international scil animal care company. Dr. Klenner is an instructor for online courses about laboratory quality assessment and management for the Veterinary Information Network and regularly lectures at national and international conferences. She is chair of the laboratory standards committee of the European College of Veterinary Clinical Pathology (ECVCP). Dr. Klenner’s main interests are haematology, acute-phase proteins and quality assurance in laboratory diagnostics.