Abstract Deaths by homicidal poisoning, which are recognized as such, titute a very small fraction of all poisoning deaths in the United States representing, according to this book, 14 poisonings per 10 000 homicides. The caveat however is critical, since as the author points out, murder by poisoning can be among the most difficult murders to identify. Of the cases discussed in this book, the vast majority involve the use of a classical poison, such as arsenic, cyanide, or strychnine, which makes them easier to identify. Poisoning using a drug which a decedent has been prescribed or has had access to, however, certainly cannot be distinguished from a voluntary ingestion on the basis of the toxicology laboratory result, and the only people who know whether the diug was willingly ingested by the victim, or administered by a poisoner, are usually these two actors, one of whom is invariably dead.