{ "background": "Municipal infrastructure asset management systems (MIAMS) are critical for sustainable urban development in sub-Saharan Africa, yet their adoption by local government authorities remains inconsistent and poorly understood. Existing studies often rely on self-reported survey data, lacking rigorous causal evidence on the factors that drive or hinder implementation.", "purpose and objectives": "This working paper presents a methodological evaluation designed to measure the causal effect of a targeted technical support intervention on the adoption rates of MIAMS. The primary objective is to quantify the adoption elasticity with respect to structured diagnostic support.", "methodology": "We conducted a randomised field trial involving 48 municipalities. Municipalities were randomly assigned to a treatment group receiving a structured adoption diagnostic and technical support package, or a control group. Adoption was measured via a verified implementation index. The treatment effect was estimated using an intent-to-treat analysis with the model: $Yi = \\beta0 + \\beta1 Ti + \\mathbf{X}i'\\gamma + \\epsiloni$, where $Yi$ is the adoption index, $Ti$ is the treatment assignment, and $\\mathbf{X}_i$ is a vector of baseline covariates. Robust standard errors were calculated.", "findings": "Preliminary analysis indicates a positive and statistically significant treatment effect. Municipalities receiving the diagnostic intervention showed a 22 percentage point increase in the average adoption index score compared to the control group (95% CI: 14 to 30 pp). The diagnostic revealed that data standardisation protocols were the most frequently cited barrier to full system implementation.", "conclusion": "The randomised trial confirms that targeted, diagnostic-driven technical support can substantially accelerate the adoption of municipal asset management systems. The methodology provides a robust framework for evaluating similar engineering management interventions in resource-constrained settings.", "recommendations": "Future roll-out programmes for MIAMS should integrate a structured diagnostic phase to identify and address specific institutional and technical barriers prior to full implementation. Funding for such systems should be contingent on the completion of this diagnostic to