The climate crisis has evolved into a multidimensional global challenge that affects not only ecological systems but also economic, social, and administrative structures. This transformation has directed public administration toward a new paradigm centered on sustainability. The approach known as green public administration aims to integrate environmental sensitivity into all stages of governance—decision-making, planning, and implementation—while prioritizing environmental, ethical, and social justice principles. Conceptually, it is rooted in the sustainable development debates of the late 20th century and the Brundtland Report’s notion of a ‘common future’. Green public administration advocates for environmental policies to be treated not as a subsidiary domain but as a core axis influencing the entirety of public governance. This approach revolves around themes such as energy efficiency, carbon neutrality, circular economy, environmental justice, and citizen participation. In practice, local governments have become key actors in this transformation, particularly in cities responsible for a large share of global carbon emissions. Cities such as Barcelona, Amsterdam, Copenhagen, and New York serve as prominent models through their initiatives in green infrastructure, sustainable transportation, participatory environmental planning, and digital data governance. The success of green public administration depends on the robustness of democratic governance and the degree to which social justice is achieved. Citizen participation, transparency, and accountability emerge as essential principles that enhance the effectiveness of environmental policies. Circular economy practices and carbon-neutral strategies promote efficient resource use while contributing positively to economic productivity. However, the institutionalization of green public administration often faces challenges such as financial constraints, bureaucratic resistance, lack of political will, and persistent social inequalities. At the same time, digitalization and AI-supported smart city technologies offer innovative solutions for environmental monitoring and resource management. Ensuring that these technological tools are applied within ethical and socially inclusive frameworks strengthens the democratic legitimacy of green public administration. In conclusion, green public administration represents a holistic paradigm that redefines public administration in response to the global climate crisis. Its success depends on innovative financing mechanisms, strong political leadership, enhanced institutional capacity, multi-level governance, and effective citizen participation. The innovative practices developed by local governments demonstrate that green public administration has become both a framework for environmental sustainability and a cornerstone for democratic transformation.