Abstract Diatoms possess a number of attributes which contribute to their suitability as biological indicators. They are highly sensitive to water chemistry changes, abundant in aquatic environments, largely cosmopolitan in distribution, less habitat dependent than macroinverte-brates and have a well-studied taxonomy and ecology. Furthermore, the preservation of diatom valves in lake sediments means that they can provide otherwise unavailable baseline data which can be used to assess and contextualize human impacts on aquatic ecosystems. The value of diatoms as bioindicators in contemporary and palaeolimnological studies has been well established overseas. Despite this, they have been under-utilized in Australia. This paper outlines some of the applications and potential for the use of diatoms as biological indicators in Australia.