Tropical forests play a crucial role in the global carbon budget, accounting for more than half of terrestrial net primary production and storing around 40% of plant biomass, yet unprecedented climate shifts are predicted this century in tropical regions. Tropical forests around the world are increasingly experiencing significantly warmer climates relative to their recent historical climate regimes. Despite this urgent climate change context we have little understanding of what current temperatures are experienced by leaves, the temperature at which the main processes controlling productivity such as photosynthesis and respiration occur, and in particular the limits of thermal tolerance for tropical forest species still relatively unknown. This knowledge is needed to predict response to climate change in these forests over the coming decades. Current and predicted temperature rises are far more rapid than experienced in the recent past and currently-established trees will experience these new climatic conditions. Therefore, the performance and persistence of existing tropical forest trees over this century depends on their ability to either tolerate warmer climates, acclimate their physiology to higher temperatures or, via dispersal, migrate to new climates. Elevation gradients provide ideal natural laboratories for investigating temperature responses of montane forest species. There is now a set of elevation gradient studies set up across the global tropics to study temperature responses of tropical forest trees. Here we report on early findings from these key studies, focusing on the fundamental energy balance of tropical leaves, on plant growth, physiology and survival and on plant-soil interactions. The aims of this symposium are -To synthesize and integrate ongoing research on elevation gradients across the global tropics in order to assess current and future tropical forest responses to changes in temperature at different locations, for plants of different ages, successional stages and across a wide range of species. Particular focus will be given to temperature responses of tree growth, both mature and juveniles, photosynthesis, respiration, leaf temperature and thermal tolerance, with some integrated studies also addressing soil and plant processes together. -To gather members of the scientific community currently investigating temperature responses of tropical forest in order to share findings, methodologies, challenges and developments within this community, with a view to better fundamental understanding and improved model-based prediction under future climate scenarios.