Since the discovery of human serum paraoxonase (PON1), the enzyme has been the subject of various fields of research. Initially, PON1 was identified as an enzyme capable of hydrolysing organophosphate compounds, but there is a growing body of evidence that PON1 plays a role in lipid metabolism and the onset of cardiovascular disease. Still, the precise mechanism by which PON1 functions in vivo remains to be clarified. Here we will briefly review developments in the field of PON1 research which merit further attention.