Melissa Block joined NPR in 1985 and has been hosting All Things Considered since 2003, after nearly a decade as an NPR correspondent.
Rob Stein is a correspondent and senior editor on NPR's science desk.
In his reporting, Stein focuses on the intersection of science, health, politics, social trends, ethics, and federal science policy. He tracks genetics, stem cells, cancer research, the obesity epidemic, and other science, medical, and health policy news.
Before NPR, Stein served as The Washington Post's science editor and national health reporter for 16 years, editing and then covering stories nationally and internationally.
Earlier in his career, Stein spent about four years at NPR's science desk. Before that, he served as a science reporter for United Press International in Boston and the science editor of the international wire service in Washington.
Scott Horsley is a White House correspondent for NPR News. He reports on the policy and politics of the Obama Administration, with a special emphasis on economic issues.
The 2012 campaign is the third presidential contest Horsley has covered for NPR. He previously reported on Senator John McCain's White House bid in 2008 and Senator John Kerry's campaign in 2004. Thanks to this experience, Horsley has become an expert in the motel shampoo offerings of various battleground states.
Horsley took up the White House beat after serving as a San Diego-based business correspondent for NPR where he covered fast food, gasoline prices, and the California electricity crunch of 2000. He reported from the Pentagon during the early phases of the wars in Iraq and Afghanistan.