But he says there are challenges, including the difficulty in getting the plan approved by the United States Congress.

VOA: standard.2009.12.11

Waskow says the major challenges created for many poor countries by climate change, calls for long-term investment.

VOA: standard.2009.12.11

Gun control advocates acknowledge there will be more legal challenges by gun rights groups, but they remain optimistic most gun laws in the U.S.

VOA: standard.2010.07.06

International relief efforts have struggled to overcome the enormous logistical challenges of bringing food, water and temporary shelter to the hundreds of thousands of people left homeless by the earthquake.

VOA: standard.2010.01.26