La Niña has a number of both positive and negative developmental impacts. These include impacts on health, livelihoods, infrastructure, water security and economic growth. La Niña is part of ENSO (El Niño-Southern Oscillation), a climate phenomenon, consisting of the El Niño, neutral, and La Niña phases. La Niña usually occurs following an El Niño event. La Niña causes opposite conditions to those associated with El Niño. Thus, areas experiencing drought during El Niño are likely to experience flooding during La Niña. Likewise, areas that have experienced excessive rainfall during El Niño, are likely to experience drought during La Niña. According to a paper produced for DFID, ‘no two La Niña events will be the same – the timing and magnitude of events differs considerably. Geographically, the majority of the literature on the impact of La Niña identified during this rapid literature review focuses on countries in Southeast Asia. In particular, there are several rigorous research studies on the linkages between La Niña and agricultural production. There is less coverage of Sub-Saharan Africa and the MENA (Middle East and North Africa) region. The literature on the impacts of La Niña focuses predominantly on the humanitarian impacts of the phenomenon, rather than on the developmental impacts. Moreover, there is limited evidence of causality, suggesting a need for more rigorous studies on the linkages between La Niña and development impacts. A significant number of the studies available are quantitative, suggesting that there is also a need for more mixed methods research to enable a more in-depth understanding of the correlations identified by the existing quantitative research. In addition, a number of the studies on this topic are of low quality.