The main goal of this paper is to discuss the dynamics of public debt servicing – both domestic and foreign – in Zambia, tracing the trends, reforms and challenges over the period from 1964 to 2015. The paper shows that the exceptional rise in public debt servicing obligations in Zambia over the period under review has been principally due to high domestic and foreign interest rates, frequent debt rescheduling at commercial rates, and capitalisation of non-liquidated service obligations at commercial rates. Also revealed in the paper is the fact that prior to 2005, Zambia experienced severe public debt servicing problems which eased after 2006 owing to debt relief initiatives and an economic rebound. Among the government debt service reforms discussed in the paper are structural adjustments in foreign exchange management, fiscal and monetary reforms, and aggressive engagement of traditional creditors. Primary among the identified challenges of public debt servicing in Zambia was the insistent economic crises that dogged the country during the study period. Notwithstanding the current public debt service sustainability and remarkable economic performance that characterise the country today, the paper found that the recent contraction of nonconcessional loans by the state poses a threat to debt service sustainability in future. Hence, the paper recommends, among other things, for aligning of public sector infrastructure spending with revenues to ensure budget sustainability, and to continue diversifying the economy to minimise the impact of external commodity price shocks on the economy.