This study assessed implementation status of collaborative TB/HIV services in Addis Ababa City Administration aiming to promote better implementation strategies. The study employed mixed research methods and was descriptive. The study design used both quantitative and qualitative data using structured questionnaires and semi-structured interview guides, respectively. The study population for the quantitative design included 1,683 TB/HIV patients from 10 conveniently selected health facilities: Zewditu and Menelik Hospitals, health centres of Lideta, Yeka, Kazanchis, NifaSilk-Lafto-No1, Woreda-7, Kality, Bole and Gulele. All the patients who were on their follow-up cares during the data collection period were interviewed. Participants for qualitative design were 1,650 TB/HIV patients for short answered questions; 8 FGDs among patients; interview of 10 TB/HIV care facility coordinators/health workers and one regional TB/HIV care coordinator, all purposively selected. Quantitative data was analysed using SPSS 15.0, while qualitative data were thematically analysed manually. Majority of HIV patients (92.8%) self-reported that they had been screened for TB; of which, 11.2% were diagnosed for active TB during their follow-up cares. Whereas, 87.1% of TB patients had been offered for HIV test; 79.8% tested; 20.2% tested positive. Knowledge on TB and HIV diseases, transmission and prevention was found to be low. However, participants appreciated the support of the healthcare delivery system in improving their health. Collaborative TB/HIV activities brought additional on-the-job training for healthcare workers; improved flow of logistics and re-arrangement of infrastructures of facilities. The study revealed that, implementation of collaborative TB/HIV activities in Addis Ababa need boosting. The study recommends the need for coordinated efforts of all stakeholders for improving implementation of collaborative TB/HIV care services, as identified by this study. The contribution of this study developed pocket-guide for healthcare workers on collaborative TB/HIV care services, which provides guidance in promoting better TB/HIV care / Health Studies / D. Litt. et Phil. (Health Studies)