One of the most rapidly developing areas of organellar biology, and one with major involvements in biochemical pharmacology, is that of peroxisomal function. In this commentary, several recent research findings in this area are described, along with their significance in relation to the metabolism of drugs and xenobiotics. Topics that are covered include the peroxisome proliferation caused by a wide variety of chemical compounds, the metabolic implications of this phenomenon, interactions between peroxisomal transcription factors and the eicosanoids, and the close relationships between peroxisomal metabolism and the control of functional damage caused by oxygen free radicals. Examples are also provided on interactions between peroxisomal function and such diverse drug groupings as analgesics, anti-inflammatories, nutritional ingestants, insecticides, antifungals, herbicides, and plasticisers. It is concluded that the peroxisome plays a central role in the metabolism of many drugs, displays a significant potential in furthering an understanding of pharmacological mechanisms, and is deserving of greater emphasis in future research considerations in this area.