In a recent Lahore high court judgement, honourable Justice Tariq Salim Sheikh directed the Punjab government to bring all brick kiln factories under the remit of the law. It should ensure no brick kiln factory can excavate soil from the surface or beneath the surface unless or until it obtains permission from mines and minerals department as the court held that the resources beneath or on the surface belong to the government. In this case, I was appointed as amicus curiae wherein I assisted the court and delineated the concept of public trust doctrine, which the court adopted in both letter and spirit. The ancient laws of Byzantine Emperor Justinian contained the concept of “res communis,” which has come to be known as the Public Trust Doctrine. It implied that certain properties like air, running water, the sea and the seashores were common property shared by all citizens. The title to these essential resources vested in the State in trust for the benefit of the general public. The State was, thus, bound to protect them for their uninterrupted use. In America, the Public Trust Doctrine was applied in the American case Illinois Central Railroad v Illinois, 146 US 387 (1892). Illinois wanted to give Chicago’s entire lakeshore to a private railway company. The Supreme Court held it could not do so as the lake and the ground were protected by “a title held in trust for the people of the state so that they may enjoy the navigation of the waters, carry on commerce over them, and have liberty of fishing therein free from obstruction or interference of private parties.” In our country, Ms Shehla Zia and others v. WAPDA (PLD 1994 SC 693) is the landmark case on environmental jurisprudence. It was public interest litigation in which the petitioners challenged the construction of a grid station by the Water and Power Development Authority (WAPDA) in their residential area on the ground that the electromagnetic field created would pose a threat to their health. The Supreme Court of Pakistan observed a balance should be struck between the rights of the citizens and the plans executed by the Authority for the welfare, economic progress and prosperity of the country and if there were threats of serious damage, effective measures should be taken to control it. This case is significant for two reasons. Firstly, it held the right to life should be interpreted to encompass environmental rights. Secondly, it laid the foundation for the rule of the Precautionary Principle, akin to the Public Trust Doctrine. The Public Trust Doctrine is the foundational principle of sustainable development, which is cherished by every nation Sindh Institute of Urology and Transplantation and others v Nestle Milkpak Limited (2005 CLC 424) was the first case in Pakistan in which the Sindh High Court applied the Public Trust Doctrine directly. The defendant, a multinational company, started the construction of a water bottling plant close to Karachi aimed at saving transportation costs in supplying bottled water to the city by tapping into and making free use of the sub-soil water/aquifer underlying the land reserved for establishing health and educational institutions to be termed “Education City.” The plaintiffs filed a suit seeking a declaration that it was illegal and prayed that pending its disposal an interim injunction be issued restraining it from proceeding with its project. The defendant inter alia contended that under Section 7 of the Easements Act, 1882, every owner of the land had an absolute right to enjoy and dispose of his immovable property. There was no law for the time being in force in Pakistan prohibiting it from using the sub-soil water by the installation of tube-wells in its land and extract any amount of water that it required. The Court held as under: “No civilised society can permit unfettered exploitation of its natural resources by anyone particularly in respect of the water, which is a necessity of life. Groundwater is a national wealth and belongs to the entire society. It is a Nectar, sustaining life on earth and without water, the earth would be desert…It is well-settled natural resources like air, sea, waters, and forests are like public trust. The said resources being a gift of nature, they should be made freely available to everyone irrespective of the status. ‘Doctrine of Public Trust’, as developed during the days of ancient Roman Empire, enjoins upon the Government to protect the resources for the enjoyment of the general public rather than to permit their use for private ownership or commercial purposes.” Our jurisprudence on this concept is continuously developing. In Maple Leaf Cement Factory Ltd v Environmental Protection Agency and others (PLD 2018 Lah. 255), a case in which the Petitioner challenged the Signal Free Corridor Project in Lahore, a Full Bench of this Court observed: “The corpus of environmental laws has a singular purpose of protecting life and nature, including the international environmental principles of sustainable development, precautionary principle, environmental impact assessment, inter and intra-generational equity and public trust doctrine. Our existing jurisprudence (led by the landmark judgment of Shehla Zia case, PLD 1994 SC 693) rests environmental justice on right to life (Article 9) to mean a right to a healthier and cleaner environment. Time has come to move on. To us environmental justice is an amalgam of the constitutional principles of democracy, equality, social, economic and political justice guaranteed under our Objectives Resolution, the fundamental right to life, liberty and human dignity (Article 14), which include the international environmental principles of sustainable development, precautionary principle, environmental impact assessment, inter and intra-generational equity and public trust doctrine.” The Public Trust Doctrine is the foundational principle of sustainable development, which is cherished by every nation. Sustainable development is most often understood in terms that it is the development that meets the needs of the present without compromising the ability of future generations to meet their own needs. The writer is a constitutional lawyer, human rights activist and a teacher