For four decades, Father Joe has been a beacon of hope for some of Bangkok's poorest children. Now two filmmakers are hoping to document his inspiring life

Klong Toey, Thailand’s biggest urban slum, is comprised largely of rickety lean-tos. Some of these look onto fetid sewers; others have open doorways leading onto the area’s complicated tangle of sois. As children play in these densely populated streets, many a mother or a grandmother etches out a living through jobs such as selling noodles or mending clothes.

This Wednesday the world will mark World Aids Day. Observed on the first of December each year since 1987, the day is dedicated to raising awareness of the AIDS pandemic caused by the spread of HIV infection. Between 1981 and 2007, AIDS has killed more than 25 million people and there an estimated 33 million people living with HIV, thousands of those are children. In Bangkok's slum community of Klong Toey, sixty children are all HIV positive are cared for at the Mercy clinic, many of them are orphaned or abandoned.

For three decades, Father Joe Maier has made it his mission to take in the throwaway youths of Bangkok's largest ghetto.

In the sprawling Bangkok slum area where Father Joe Maier has worked for decades, his organization has often been called on to help people after fires devastated flimsy homes.

A Catholic priest in the slums of the Thai capital puts into practice the teachings of Polish Jewish pedagogue Janusz Korczak