Many children with developmental delays need early intervention services but do not receive them. Developmental screening provides the impetus for identification of delays and service referrals but is not used consistently across all early childhood education settings. We used an implementation science framework to examine attitudes and engagement in a developmental screening program across three U.S. early childcare centers. Teachers demonstrated adequate knowledge of screening following training in the screener and were highly engaged in the screening process. Teachers' positive attitudes toward screening increased yet perceived barriers to regular use of screening in their practice remained unchanged. Family participation in the screening process varied across centers and suggested a trend between family income and participation. Future research is needed to target pervasive barriers to teachers' use of screening, such as perceived difficulties in engaging parents in the screening process.