Hansjörg Eichler held several positions in European herbaria in the post-war period where his research centred on what became a life-long interest in hydrophytes, particularly the genera Ranunculus and Hydrocotyle. In 1955 he was appointed Keeper of the South Australian state Herbarium, arriving to find a moribund institution. With his rigorous grounding in classical taxonomic and traditional herbarium procedures he determined to bring the Adelaide Herbarium up to international standards and respected in international scientific circles. His nomenclatural expertise was greatly relied on by other botanists in Australia. In his taxonomic work Eichler took an Australia-wide perspective, somewhat unusual in the state-based herbaria in Australia at the time. He was strong advocate for the publication of a new flora of Australia, serving on various committees which led to the establishment of the Australian Biological Resources Study and the eventual Flora of Australia project. Volume 18 of the Flora of Australia is dedicated to him. In 1993 the Australian Systematic Botany Society established the Hansjörg Research Fund in his honour. His personal herbarium of over 24,000 specimens in now in the State Herbarium of South Australia and the Australian National Herbarium.