Introduction: World Health Organization recommends screening of household contact as a key to improve detection of tuberculosis cases. Ethiopia’s current tuberculosis household contact investigation strategies rely on symptomatic contacts attending health facilities for investigation. This approach has not led to the detection of additional tuberculosis (TB) cases; alternative approaches have to be considered. The purpose of the research was to develop guidelines in endorsing the implementation of a community based household contact investigation program in Addis Ababa. Methods: A mixed method research using sequential exploratory design was conducted in Addis Ababa. In the first phase, qualitative data collection and analysis methods were used to formulate intervention approach and in the second phase, a quantitative random controlled trial was conducted, with the purpose of comparing the proposed intervention measures with routine household contact tuberculosis investigation. Frequencies and logistic regression analyses were used to determine the relative risk and associated factors. Thematic analysis was used for qualitative data analysis. Results: The in-depth interview and focus group discussion findings identified themes namely household contact investigation (HHCI) implementation, misconceptions on HHCI, challenges with HHCI Approaches, opportunities for HHCI provision, contributing factors associated with household involvement, strategies for effective HHCI service and partnerships with health bureau. In phase two, the study reported that the prevalence of TB was 7.1% among the intervention group compared to 1.9% in the control groups at the end of first year follow-up. Nine guidelines were developed to support the household contact investigation system. Conclusion: The passive case detection strategy of contact investigation did not find more cases, and tuberculosis patients and their family contacts were not satisfied with this method. However, the proposed community-based strategy shows that more TB cases can be detected by using existing medical staff. Therefore, an approach that makes the service more accessible is significant and the recommended community based TB household contact tracing approaches needs to be scaled up for its performance towards identified missed cases and enhance patient and their household contacts involvement. / Health Studies / D. Litt. et Phil. (Public Health)