American, British and Dutch planes dropped more than 1,500 cluster bombs on the province in three months, leaving an estimated 20,000 unexploded bomblets on the ground.
Last month, when the BBC's "Face the Facts" programme visited Kosovo, its reporters found unexploded cluster bomblets at the site, though farming had resumed and children were at play.
These are the most likely to fail, leaving deadly unexploded bomblets.
Cluster munitions which release bomblets to cover a wide area are banned or tightly restricted by an international convention.
The UN estimates that 98% of victims of cluster munitions, explosive weapons that scatter bomblets across a wide area, are civilians.
But cluster bomblets, by their sheer number, are likelier to kill and wound civilians, and make the post-war cleaning-up job even harder.
Moreover, deadly cluster bomblets, supplied to Israel by America, still clutter south Lebanon.The Cedar revolution that erupted after the February 2005 assassination of Rafik Hariri, a former prime minister who had turned hostile to Syria, had seemed to boost American influence.
Opponents of cluster munitions say they are an indiscriminate weapon when they go off; and that unexploded bomblets turn the target area into a virtual minefield.
HRW reckons the number of bomblets runs into the billions.
Its seven leaders were arrested after the explosion of 459 bomblets in 63 of the country's 64 districts, all within 40 minutes.
Far more have suffered loss of their livelihoods, with farmlands clogged by Israeli cluster bomblets and businesses bankrupted by the collapse of tourism.
