The chronosystem is a concept from the ecological systems theory developed by Urie Bronfenbrenner. It refers to the dimension of time in a person's environment, highlighting how life events and transitions influence development. This includes changes in family structure, socio-economic status, or significant historical events that can impact an individual over time. In the chronosystem, both the timing and duration of these events are important. For example, experiencing a divorce during childhood may have different effects than during adolescence. Understanding the chronosystem helps researchers and practitioners recognize how temporal factors shape individual experiences and development.