Students who are frequently absent from school ('non-attenders') are considered to be 'at risk'. State education departments have recently begun to improve their collection of student absence data, often to contribute to the development of performance standards for schools. This paper presents a summary of data from the Term 2 collection in South Australian government schools in 1997 and 1999. the data were combined with student information, which allowed examination and comparison of attendance patterns for different groups of students. The author provides details about which students were absent in those years, the frequency of students' absences, which students had no absences, and the stated reasons for students' absences. The author recommends that no single attendance standard can be set for schools, based on the differential targets shown for different groups of students.