Several studies emphasized the importance of developmental and readiness testing as that wouldrnenable early identification of those who need support or further assessment. Besides, researchesrnshowed that children who were at risk or who experienced delayed development when passedrnthrough early intervention they manifested positive gains in development. In this connection, thisrnstudy was conducted with three objectives in mind. The first one was screening forrndevelopmental delays among infants and young children of Addis Ababa; the second one wasrnidentifying risk factors associated with global developmental delay; and the third objective wasrnconducting intervention with some developmentally delayed infants and children. To achievernthese objectives descriptive survey and quasi-experimental designs were implemented. A samplernof 1,062 infants and young children were randomly selected from Bole, Addis Ketema and Kolfernsub-cities. Infants and young children’s development was assessed by using Ages and StagesrnQuestionnaire – Amharic version. Besides, the characteristics of home environment, maternalrnand child conditions were gathered with the questionnaire set for this purpose. Followingrnscreening for developmental delays, three months intervention was carried out in two randomlyrnselected sites. A total of 29 participants were involved in the treatment group and 19 participantsrndid take part in comparison group. Data on children’s developmental status were collectedrnbefore and after intervention. The data collected were analyzed through logistic regressionrnanalysis, MANOVA, t-test, frequencies and percentages. The results of the investigation revealedrnthat 28.13% of infants and young children involved in this research revealed globalrndevelopmental delay and more delayed development was observed in fine motor domain asrn30.53% of children showed delayed development in this domain. From the risk factors evaluatedrnin this research maternal age, low birth weight, physical punishment, unavailability of playingrnmaterials, exposure to illness and family size were found to be significantly associated withrnglobal developmental delay. However, when predictor variables entered the statistical model thernproportion of variance explained by the variables examined was very small in most cases and thernlargest one was 19.9% which was the explained variance on communication scores for infants ofrn18 months age interval. The results of the intervention study showed that infants and youngrnchildren in comparison group performed better than those in the treatment group. Based on thernfindings obtained some recommendations are made