Grenada is 1 of 15 developing countries in Caribbean Community known as CARICOM. The infrastructure capital projects in these developing countries are plagued with an array of issues: unethical practices, inadequate supervision, lack of transparency and accountability, inadequate monitoring and evaluation, cost overruns, and inefficiencies. In the 1980s and 1990s, the International Monitory Fund and World Bank introduced a balanced scorecard engineered under the structural adjustment program, but it was unable to improve infrastructure project efficiencies. This qualitative case study sought to understand the role of management key performance indicators (KPIs) on public sector infrastructure capital project efficiency on the island of Grenada. An institutional assessment and development framework and a classical management theoretical framework methodology were used to explore the effects of management KPIs on public sector infrastructure capital projects efficiencies in developing countries. The research incorporated a constructivist philosophy that underpins the evaluation and perception of the government, the National Water and Sewerage Authority (NAWASA), project teams, systems, and stakeholders. A purposive sampling strategy with elements of snowballing was used to obtain 12 representative participants for interviews, and a systematic approach of transcribing, coding, and thematic analysis was done. Findings indicate inadequacies in the BSC performance measure system on infrastructure projects, which justifies the use of comprehensive management KPIs. Positive social change implications of this study include recommendations for comprehensive management KPIs and policies to improve public sector infrastructure project efficiency in Grenada.