Each September marks Attendance Awareness Month, which recognizes the important role attendance plays in supporting children's development, learning, and academic achievement. Research has examined this role extensively for attendance during children's K-12 school years. For children's early years there is a wide range of research exploring topics related to the time they spend enrolled in programs, including in full- versus part-day programs, their age at enrollment, and the number of years of program enrollment. However, there is less research asking: once children are enrolled in a given program, how often do they attend and how does attendance relate to their developmental and school outcomes? This Topic of Interest highlights research that addresses those questions. (author abstract)