Background and Objective: Since 2010, World Vision (WV) has trained community health workers (CHWs) in vulnerable communities in Palestine to deliver timed, behavioral change communication on health and nutrition (H&N) for the First 1000 Days to mothers through scheduled home visits. This approach was later enhanced through integrating components on early leaning and stimulation to align to World Health Organization framework for nurturing care for early childhood that was issued in 2018. The objective of this research is to test the effectiveness of this enhanced integrated approach on holistic child development. Methods: Twenty-six communities were randomized to control or intervention groups.238 women were assigned to the Intervention group and received the integrated package and 231 were assigned to the Control group and received only the H&N intervention, an average of 25-30 home visits were delivered by the CHWs to all participating mothers. Data were collected from both groups at baseline and end-line using standardized questionnaires, Ages and staged questionnaires (ASQ) were used to assess child development. Intra-cluster correlation coefficients were calculated for each ASQ domain at each time point. A mixed linear model was also applied. Mean ASQ scores for the Intervention and Control arms for each developmental domain and time-point were adjusted. Results: At 12 months of age, mean ASQ scores for 4 of the 5 developmental domains were higher in the Intervention Group than Control [Communications 59.5 vs 55.9, Personal Social 88.8 vs 79.0, Problem Solving 58.6 vs 52.8, Fine Motor 57.7 vs 53.1] (p<0.05). The effect sizes of the integrated package on the developmental domains range from 0.4-0.8, whereas those for stand-alone early child development interventions tend to range from 0.2-0.5. Conclusions: The integrated approach is more effective on children’s ECD during the first year of life than standalone interventions.