Today's tour of the central Sao Paulo area was meant to help the prince learn about programmes aimed at helping addicts leave drugs and find work.
As the prince strolled through the streets accompanied by local officials and a heavy security detail, barefoot women clutching improvised crack pipes shouted that they wanted to get closer.
One of the men in the program is Helio Roque, who earns USD 7 a day cleaning streets. He clambered atop a trash can to grab a glimpse of the prince.