{ "background": "Municipal infrastructure asset management in developing nations often lacks robust, data-driven diagnostic tools. In Ghana, systemic inefficiencies persist due to fragmented data and a paucity of analytical frameworks capable of disentangling institutional from operational performance factors.", "purpose and objectives": "This paper develops and applies a multilevel regression modelling framework to diagnose efficiency determinants within municipal infrastructure systems. The objective is to quantify the variance in asset management performance attributable to different administrative levels and identify key drivers of efficiency gains.", "methodology": "A hierarchical dataset was constructed from municipal records, covering asset inventories, maintenance expenditures, and condition ratings. A two-level random intercepts model was specified: $y{ij} = \\beta{0} + \\beta X{ij} + u{j} + e{ij}$, where $i$ denotes assets and $j$ denotes municipalities. Model estimation used restricted maximum likelihood with robust standard errors to account for heteroscedasticity.", "findings": "Municipal-level random effects ($uj$) accounted for approximately 32% of the total variance in asset condition scores, indicating significant institutional heterogeneity. A one-unit increase in the standardised maintenance planning index was associated with a 0.15 improvement in asset condition (95% CI: 0.09, 0.21), holding other factors constant.", "conclusion": "The analysis confirms that efficiency in municipal infrastructure management is substantially influenced by institutional factors at the municipal level, beyond asset-specific characteristics. The multilevel approach provides a powerful diagnostic for targeting interventions.", "recommendations": "Asset management policy should mandate the collection of standardised, hierarchical data. Training programmes for municipal officers should focus on improving planning and budgetary processes, as these were identified as significant levers for efficiency.", "key words": "infrastructure asset management, multilevel modelling, efficiency diagnostics, municipal engineering, developing countries", "contribution statement": "This paper presents a novel application of multilevel regression to decompose efficiency variance in infrastructure systems, providing