Long-term ecological data are critical for informing long-term trends in biodiversity and trends in environmental change. The Terrestrial Ecosystem Research Network (TERN) is a major initiative of the Australian Government and one of its key areas of investment is to provide funding for a network of long-term ecological research plots around Australia (LTERN). This book highlights some of the temporal changes in the environment and/or in biodiversity that have occurred in different ecosystems, ranging from tropical rainforests, wet eucalypt forests and alpine regions through to rangelands and deserts. Many important trends and changes are documented and they often provide new insights that were previously poorly understood or unknown. These data are precisely the kinds of data so desperately needed to better quantify the temporal trajectories in the environment and biodiversity in Australia.