New Delhi (CNN) -- On a recent trip home to India, I heard a German man on my flight remark to another passenger that he'd taken his son on a tour of a Kolkata slum. I believe the man was well-intentioned -- he wanted his child, accustomed to a comfortable existence, to get a firsthand look at how millions of poor people live. Later, I discovered that slum tours in India are often organized and can cost money. Reality Tours and Travel takes tourists on slum and sightseeing tours in Mumbai. A walking tour of Dharavi, Asia's largest slum, costs only $9. For about $135, five people get a nine-hour car tour of Dharavi, the red light district of Kamathipura, as well as other more traditional tourist areas.
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The charitable Salaam Baalak Trust runs a city tour in New Delhi
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Tourists walk through the streets of Paharganj, a poor neighborhood
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Former street kids act as guides through a maze of congested lanes
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Poverty tours have sparked controversy
@placeholder founders say the tours were set up "primarily to show the positive side of the slums and break down negative stereotypes about its people and residents" who occupy cramped huts in unending stretches of squalor.