As a host, Siegel has reported from Western Europe, Eastern Europe, and Israel. He now concentrates on domestic stories.

During the fall of 1992, Siegel took a short leave from the show to anchor Talk Of The Nation®, NPR's midday news-talk program.

Before joining All Things Considered in 1987, Siegel served for four years as director of NPR’s news and information department, overseeing production of NPR's newsmagazines All Things Considered and Morning Edition®, as well as special events and other news programming. During his tenure, NPR launched its popular Saturday and Sunday newsmagazine, Weekend Edition. Siegel joined NPR in December 1976 as an associate producer, and was appointed public affairs editor in 1977 and senior editor in 1978. In 1979, Siegel was chosen to open NPR's London bureau, where he worked as senior editor until 1983.

From 1971 to 1976, Siegel worked for WRVR Radio in New York City as a reporter, host, and director of news and public affairs. While at WRVR, he was one of a team that received an Armstrong Award for the series "Rockefeller's Drug Law." Before going to WRVR, he was morning news reporter and telephone talk show host for WGLI Radio in Babylon, New York.

Siegel shared in NPR's 1994/95 Alfred I. duPont-Columbia University Silver Baton Award for "The Changing of the Guard: The Republican Revolution," NPR's coverage of the first 100 days of the 104th Congress. His coverage of the peace movements in East and West Germany earned him a 1984 Alfred I. duPont-Columbia University Silver Baton Award for excellence in broadcast journalism. His other awards include the National Mental Health Association's 1991 Mental Health Award for his interviews conducted on the streets of New York in an All Things Considered story, "The Mentally Ill Homeless."

A graduate of Columbia University, Siegel's career in radio began at the college radio station, WKCR-FM, where he anchored coverage of the 1968 Columbia demonstrations. The station's work received an award from the Writers Guild of America East.

Siegel is the editor of The NPR Interviews 1994, The NPR Interviews 1995, and The NPR Interviews 1996 — annual compilations of NPR's most popular radio conversations.