Globally, 2.1 billion people live without access to safe water, and about 159 million people collect their drinking water directly from surface water sources. This issue is particularly prominent in water-stressed areas, such as India, which has a rural population of around 700 million, 63 million of whom do not have access to clean water. Contaminants of Emerging Concern (CECs), of both a chemical and biological nature, are increasingly being detected in wastewater effluents around the world. Chemical CECs include pollutants such as pharmaceuticals and personal care products, pesticides, hormones, and endocrine disruptors, and biological CECs include antibiotic resistant bacteria, pathogenic protozoans, and viruses. New technologies to remove the contaminants from water are urgently needed and photochemical approaches offer an exciting array of possibilities.