Describes the Peer Network and Dyadic Loneliness Scale (PNDLS), a new scale designed to assess simultaneously children's loneliness at multiple levels of peer relationships. Specifically, this scale measures loneliness associated with (a) lack of involvement in a social network and (b) the absence of a close dyadic friendship. Employing a sample of 209 5th-, 6th-, and 7th-grade boys and girls, the psychometric properties, interscale correlations, and preliminary validity data for the new scale are examined. Analyses revealed good internal consistency and a pattern of relationships with other loneliness, friendship quality, mutual best friendship, and sociometric social preference variables supporting the validity of the new scale.