The ultimate aim of this fellowship is to improve the ability of the Australian seasonal forecasting system by enhancing our dynamical understanding of the worlds largest source of climate variability, the El Nino-Southern Oscillation (ENSO). The impacts of ENSO events are so large that knowledge of its current phase and forecasts of its future phase largely underpin many seasonal rainfall, temperature and tropical cyclone forecasts worldwide, including Australia. Using a suite of observations and numerical models to undertake a comprehensive analysis of ENSO event precursors, initiation and predictability, this research intends to enhance skill in inter-seasonal climate forecasting and aid those sectors reliant on accurate prediction.