Constitutionalism, in the Indian context, signifies governance strictly according to the provisions of the Constitution, which acts as the supreme law of the land. It embodies the principle of limited government, where the powers of all state organs – the legislature, executive, and judiciary – are derived from and constrained by the Constitution. This concept is indeed the bedrock of India's administrative edifice, ensuring that public administration operates within a framework of legality, accountability, and public welfare.

The administrative structure in India, from the Union to the local level, draws its legitimacy and functional boundaries from the Constitution. Articles like 309-323 deal with public services, establishing the framework for recruitment, conditions of service, and the role of bodies like the UPSC and State Public Service Commissions. This ensures a merit-based, politically neutral bureaucracy, essential for impartial administration. Furthermore, fundamental rights enshrined in Part III of the Constitution act as a crucial check on administrative actions, preventing arbitrary or oppressive exercise of power. Any administrative action that violates these rights can be challenged in courts, reinforcing the supremacy of constitutional principles.

The Directive Principles of State Policy (DPSP) in Part IV, though not justiciable, provide a moral and ethical compass for administrative policy-making, guiding the state towards achieving social and economic justice. This means that administrative decisions are not merely about efficiency but also about equity and welfare. The separation of powers, judicial review, and the independent judiciary further strengthen constitutionalism by ensuring that administrative actions are subject to legal scrutiny and that the executive does not overstep its bounds. Thus, every administrative decision, policy formulation, and implementation must align with the spirit and letter of the Constitution, making constitutionalism the indispensable foundation upon which the entire administrative system of India is built and sustained.