Utah State University partnered with area Early Head Start programs to develop a measurement tool for observing, tracking, and supporting parent-child interactions that lead to positive child outcomes from infancy to age three. The primary objectives for the study are to: (1) develop a valid, reliable measure of early parent-child interaction, (2) assess the usefulness of the measure for Early Head Start staff who will observe parenting interactions, and (3) develop supporting materials in English and Spanish. To develop the initial version of this measure, parent-child interactive behaviors were defined in easily observable terms, tested by observers viewing an archive of over 1,500 videotapes of parent-child interaction, and analyzed in relation to previously measured global dimensions of parent-child interactions, children's attachment security, and children's developmental outcomes. A revised version of the measure was tested on a new sample of 200 families, with 600 new observations. The proposed measure expands Head Start's tools for tracking program effectiveness and progress towards improving parent-child interactions.