The use of military coercion is said to have been legitimate and acceptable in post - Cold War for humanitarian and international peace and security objectives. However, military interventions in intrastate struggles (sovereign states) remain contentious world over- as in Afghanistan, Ukraine, Syria, Central African Republic, DR Congo, Southern Sudan, among others. The constitutionality and legitimacy of such interventions is questionable too. Aware that international, regional and national agencies and instruments stipulate requirement for any such interventions, it is unknown whether Uganda's intervention in DR Congo and South Sudan followed them. This study intends to establish; who should intervene in the affairs of sovereign states; On which grounds should Uganda's military intervention be warranted in Congo and South Sudan,? and the applicability of the principle of non-interference in globalized age of sovereignty and human rights. Qualitative research approach and methods will be used. It will be carried out in Uganda, DRC and South Sudan, through documentary reviews and in-depth interviews.