Abstract: The pipeline transport of ammonia, a critical decarbonized energy carrier, plays a central role in the emerging ammonia economy. However, the degradation of materials in ammonia environments remains a significant challenge to the long-term sustainability of pipelines. This article provides an extensive review of global ammonia pipeline projects. The rapid expansion of ammonia pipeline infrastructure reflects increasing global energy demands and the urgency of climate control. The review consolidates essential information on the underlying causes, influencing factors, testing approaches, and protective strategies related to material degradation and pipeline failures in ammonia environments. Corrosion and stress corrosion cracking are identified as the predominant failure mechanisms for ammonia pipelines. Present safety evaluations lack standardized testing protocols and accurate real-world simulations. Protective measures, including medium regulation, surface coatings, and material enhancements, have shown potential in improving pipeline longevity but encounter hurdles in terms of cost-efficiency and scalability. The economic and environmental consequences of pipeline failures are substantial, with integrity maintenance accounting for 4.02% of overall project costs.