This review provides a comprehensive overview of past and current research on the perception of gaze behavior and its effects on observers, focusing on the gaze-cueing paradigm. It explores how perceived gaze direction influences visual attention and social cognition, particularly in infants, adults, and clinical populations. The review highlights the significant contributions of gaze-cueing research to our understanding of social cognition and attention, as well as the complex processes involved in joint attention. It discusses the neural basis of gaze perception, including the role of the superior temporal sulcus (STS) and the amygdala, and examines the development of gaze perception and joint attention in infants. The review also investigates the effects of eye contact on social interactions and the implications for social cognition in clinical populations, such as autism and schizophrenia. Additionally, it explores the use of gaze cues by nonhuman primates, highlighting the differences and similarities with human infants and adults.This review provides a comprehensive overview of past and current research on the perception of gaze behavior and its effects on observers, focusing on the gaze-cueing paradigm. It explores how perceived gaze direction influences visual attention and social cognition, particularly in infants, adults, and clinical populations. The review highlights the significant contributions of gaze-cueing research to our understanding of social cognition and attention, as well as the complex processes involved in joint attention. It discusses the neural basis of gaze perception, including the role of the superior temporal sulcus (STS) and the amygdala, and examines the development of gaze perception and joint attention in infants. The review also investigates the effects of eye contact on social interactions and the implications for social cognition in clinical populations, such as autism and schizophrenia. Additionally, it explores the use of gaze cues by nonhuman primates, highlighting the differences and similarities with human infants and adults.