India, Oct. 3 -- Every weekend, while many residents of Gurugram retreat indoors, a small group gathers in different parts of the city with gloves, garbage bags, and determination to wage a quiet battle against litter. At the centre of these efforts is Mathilde Rateria, a 38-year-old French expatriate, former journalist, and television director who has made the Millennium City her home and her mission.

Rateria first came to India eight years ago as a correspondent for French television. She says she fell in love not only with the country's landscapes and cultures, from the cleanest village in Meghalaya to the tea plantations of Munnar, but also with its people. After returning briefly to France to host an environmental show, she moved ba...