Peste des petits ruminants (PPR) is a highly contagious viral disease that severely threatens the livelihoods and food security of smallholder farmers across Africa, the Middle East, and Asia, including Ethiopia, where persistent outbreaks undermine national eradication efforts. Despite ongoing vaccination and surveillance campaigns, the continued prevalence of PPR highlights critical gaps in understanding its transmission dynamics, particularly regarding the role of animal movement, restocking practices, and spatial spread factors that have been insufficiently modelled compared to other transboundary diseases. Furthermore, there is a notable lack of integrated cost-effectiveness analyses of intervention strategies and optimal control frameworks tailored to PPR. Addressing these gaps, this dissertation develops and analyses a suite of deterministic mathematical models, incorporating novel components such as imperfect vaccination, restocked subpopulations, spatial heterogeneity, and co-infection with Sheep and Goat Pox (SGP), using epidemiological data from the Ethiopian Ministry of Agriculture and World orgnazation of animal health (WOAH). Model parameters were carefully estimated despite data incompleteness, employing nonlinear least squares and sensitivity analyses. Through rigorous qualitative and quantitative analysis, including stability assessments, optimal control characterisation using Pontryagin’s minimum principle, and comprehensive cost-effectiveness evaluations, this research reveals that combining vaccination with targeted biosecurity and movement control measures is the most effective and economically viable strategy for PPR eradication. Notably, the introduction of infected, restocked animals is shown to facilitate disease persistence, underscoring the need for integrated interventions beyond vaccination alone. The findings provide actionable recommendations for policymakers: prioritizing coordinated vaccination, movement restrictions, and enhanced biosecurity, supported by optimal allocation of limited veterinary resources. Overall, this dissertation advances the understanding of PPR dynamics and provides practical recommendations for improving disease control strategies in Ethiopia, thereby supporting national efforts toward the eradication of PPR.