This is a handbook designed to help facilitate the training of FTDTL scientists in forensic toxicology expert testimony. The information presented is a compilation of many years of testifying as an expert witness, reading and researching information, listening to many experts, and through conversations with Cliff, Peter, Jacqueline, Susan, Harold, Zinora, Cynthia, Abel, Etta, Jason and Michael. As scientists we owe it to the judicial system to be scientifically correct and forensically sound.