Considerable attention has been given to the issue of parent-professio
nal congruence, specifically in connection with reliability of assessm
ents. Concerns regarding the trustworthiness of parental assessments h
ave guided research to focus on the conventional issues of interrater
reliability and rater interchangeability. However, this conventional p
erspective may be misdirected and counterproductive. It is argued that
the focus should be the reliability of the pooled assessment informat
ion from parents and professionals. A more appropriate generalizabilit
y theoretic model, which would maximize social, ecological, and constr
uct validity, is proposed. An illustration with data from an early chi
ldhood assessment system is provided.