This chapter discusses the various aspects associated with the collection and management of forensic toxicology samples in postmortem, workplace, human performance and other types of toxicology testing. To obtain maximum information from a toxicology sample, the importance of specimen selection and proper collection cannot be overstated. Of equal importance is the manner in which toxicology evidence is handled; how it is packaged and stored. The accuracy as well as the amount of information that can be ascertained from a toxicology analysis is directly related to right collection, preservation and storage. For ease of reference, information on the choice of specimen is first grouped by the different types of specimens and then categorized by the type of analysis. A quick reference table summarized advantages and disadvantages of several specimen types in various types of investigation.