The Quaternary Period is characterised by multiple transitions between glacial and interglacial climate phases. These transitions are the most recent example of dynamic natural global change in Earth’s history. Glacial-interglacial transitions (‘terminations’) of the past 800 ka are characterized by rapid warming and associated sea-level rise of >100m. Glacial inceptions are comparatively less well documented and arguably more difficult to define, involving long-term cooling and gradual change at a global scale. Transitions offer valuable insights into the Earth system response to both abrupt and gradual change (e.g. internal feedbacks, time synchronicity, leads and lags, and interactions between different Earth system components) and differ in timing and magnitude in response to varying orbital configurations and internal system dynamics. In this session, we invite contributions that focus on the transitions between the major glacial cycles of the past 800 ka as recorded in palaeoclimate archives (e.g. ocean and lake sediments, glaciers and ice cores, speleothems, loess), simulated in computer models, or considered theoretically. In particular, the session aims to explore the timing, character and spatial response of different transitions and their associated internal and external driving mechanisms, as well as the behaviour of different Earth system components.