The focus is on quantitative measures of outcomes, with measurement defined as a means to determine the value or level of some phenomenon in a way that is quantifiable. The article first discusses what should be measured, self-report versus observational measures, important characteristics of quantitative measurement, and the selection of a measurement package. This is followed by descriptions, properties, and recommended uses for each of several instruments that measure aspects of the social climate of the family (family functioning); the marital relationship; caregiving context, parenting, and parent-child interaction; the developmental status of the child; child behavior, social-emotional functioning, and mental health; adult functioning (anxiety, anger, self-esteem, and depression); and partner abuse and child maltreatment. The article emphasizes the need to consider whether goals are relevant to the dimensions assessed, as well as the importance of considering best practices in prevention and early intervention for family violence and maltreatment as a basis for measurement selection. On the whole, the literature provides little guidance on which measure works best with what intensity or model of programming. The ability to detect change in children and families must take into account a number of factors, including the comprehensiveness of the model, the complexity of family problems, the target of the intervention, and the adequacy of the measures implemented. 66 references and appended table that summarizes information on domains, source, and cost