Microdevelopment is the process of change in abilities, knowledge and understanding during short time-spans. This book presents a new process-orientated view of development and learning based on recent innovations in psychology research. Instead of characterising abilities at different ages, researchers investigate processes of development and learning that evolve through time and explain what enables progress in them. Four themes are highlighted: variability, mechanisms that create transitions to higher levels of knowledge, interrelations between changes in the short-term scale of microdevelopment and the crucial effect of context. Learning and development are analysed in and out of school, in the individual's activities and through social interaction, in relation to simple and complex problems and in everyday behaviour and novel tasks. With contributions from the foremost researchers in the field Microdevelopment will be essential reading for all interested in cognitive and developmental science.