Problems of insect enumeration and assessment of needs are addressed in the contexts of rapid and substantial losses and changes to all key Australian terrestrial and freshwater environments and promoting awarenesss of the importance of insects. Further definition of the insect fauna and its peculiarities can aid threat alleviation and practical management to protect and conserve this unique and largely endemic biodiversity. Written for the many environmental managers and naturalists who are not primarily entomologists, the ten chapters expand from considerations of insect decline and diversity to the unique features of the Australian fauna and its characterisation. Cases and examples from throughout the world illustrate the major needs, approaches and priorities to sustaining a poorly known, diverse and ecologically varied insect heritage of global significance.