KRISTIN ANDERSON MOORE and SHARON VANDIVERE LONGITUDINAL INDICATORS OF THE SOCIAL CONTEXT OF FAMILIES: BEYOND THE SNAPSHOT (Accepted 4 February 2006) ABSTRACT. Longitudinal indicators are measures of an individual or family behavior, interaction, attitude, or value that are assessed consistently or comparably across multiple points in time and cumulated over time. Examples include the percentage of time a family lived in poverty or the proportion of childhood a person lived in a single-parent family. Longitudinal indicators reflect exposure not at a ‘‘snapshot’’ moment but over the lifecourse and may also be more reliable assessments of the family environment or experience. We highlight potential longitudinal indicators and discuss methodological issues. KEY WORDS: child indicators, family context, family well-being, indicators, longitudinal data 1. INTRODUCTION The purpose of this paper is to describe the concept of a longitudinal indicator and to present a conceptual framework for developing such indicators. The paper provides examples of existing longitudinal indicators, such as long-term poverty and welfare dependency. In addition, id describes opportunities for creating new longitudinal measures for families. In some cases, it would be possible to develop new longitudinal indicators if just a few variables were added to existing data bases; we present several such opportunities. 1.1. Definition and Importance A longitudinal indicator is a measure of a family or individual behavior, interaction, attitude, or value that is measured consistently or comparably across multiple points in time and cumulated to provide a portrait of an important aspect of family life over time. Thus, a longitudinal indicator is one type of cumulative indicator. However, unlike cumulative indicators that tally experiences or characteristics at a single point in time, longitudinal Social Indicators Research (2007) 83:55–85 Ó Springer 2007 DOI 10.1007/s11205-006-9060-8