This study aimed at understanding and investigating the lived experiences of early childhood teachers' observation practices as a professional tool. Interpretative phenomenological approach was utilized to investigate participants' experiences deeply from their lived experiences. The current study's participants consisted of five early childhood teachers selected through purposive sampling. The three-interview series involving three separate interviews with each participant was used for data collection and the data was analyzed by interpretative phenomenological analysis. The findings describe participant teachers' observation practices that provide data, how teachers convert data into information, and how they use observational data for decision-making. This study aims to draw attention to the critical role of observation in data-based decision-making and pinpoints practical implications for early childhood teachers.