This Outlook presents some stark choices for human societies. On one hand it warns that the diversity of living things on the planet continues to be eroded as a result of human activities. The pressures driving the loss of biodiversity show few signs of easing, and in some cases are escalating. The consequences of current trends are much worse than previously thought, and place in doubt the continued provision of vital ecosystem services. The poor stand to suffer disproportionately from potentially catastrophic changes to ecosystems in coming decades, but ultimately all societies stand to lose.