School attendance/absenteeism (SA/A) is a crucial indicator of health and development in youth but educational policies and health-based practices in this area rely heavily on a simple metric of physical presence or absence in a school setting. SA/A data suffer from problems of quality (reliability, construct validity, data integrity) and utility (cutoffs, aggregated data, punitive purposes). This article summarizes these problems and outlines strategies to improve SA/A data and to better define problematic and chronic school absenteeism. Findings include greater focus on unique local conditions and student/family circumstances to improve the use of SA/A data; and greater employment of sophisticated and sensitive data analytic and assessment strategies to better define problematic and chronic absenteeism across geographical regions and student groups. Implications include movement away from one-size-fits-all approaches and toward valid and targeted policy and practice approaches, better consideration of special circumstances that affect educational agencies and families, and useful demarcation points in a multi-tiered systems of support model for school attendance problems.