Decomposition is the first stage in the recycling of nutrients that have been used by an organism (plant or animal) to build its body, and are surrendered back to the ecosystem upon its death. It is the process whereby the dead tissues break down and are converted into simpler organic forms that are the food source for many of the species at the base of ecosystems. The species that carry out the process of decomposition, and feed on the ‘waste’ products produced by it, are known as detritivores, which means literally ‘feeders on dead or decaying organic matter’. Many of these decomposer species function in tandem or parallel with one another, with each being responsible for a specific stage or aspect of the decomposition process, and collectively they are known as the detritivore community. The decomposition of human remains involves a series of processes that begin immediately after death. The chemical process of decomposition is complex and involves the breakdown of soft tissue until skeletonization has occurred. The chemical processes associated with the decomposition involve identifiable changes to proteins, lipids, carbohydrates, nucleic acids, and bone. A knowledge of the types of compounds produced during decomposition and, importantly, when they are formed provides potentially valuable information about the time and nature of a death. A variety of analytical techniques, including separation and spectroscopic methods, are available to identify the compounds of interest in the field of decomposition chemistry.