When the co-worker ended his participation by taking a job in New York, Newhart continued the recordings alone, developing this type of routine. Dan Sorkin, a disc jockey at a radio station who later became the announcer-sidekick on Newhart's NBC series, introduced Newhart to the head of talent at Warner Bros. Records. The label signed him in 1959, only a year after it was formed, based solely on those recordings. Newhart expanded his material into a stand-up routine he began to perform at nightclubs. Newhart became famous mostly on the strength of his audio releases, in which he played a solo "straight man". Newhart's routine was to portray one end of a conversation (usually a phone call), playing the comedic straight man and implying what the other person was saying. His 1960 comedy album "The Button-Down Mind of Bob Newhart" was the first comedy album to make number one on the "Billboard" charts. It won the 1961 Grammy Award for Album of the Year and peaked at number two in the UK Albums Chart. Newhart also won Best New Artist. Newhart told a 2005 interviewer for PBS's "American Masters" that his favorite stand-up routine is "Abe Lincoln vs. Madison Avenue", which appears on this album. In the routine, a slick promoter has to deal with Lincoln's reluctance to agree to efforts to boost his image. Chicago TV director and future comedian Bill Daily, who was Newhart's castmate on "The Bob Newhart Show", suggested the routine to him. Newhart became known for an intentional stammer, in service to his unique combination of politeness and disbelief at what he was supposedly hearing. Newhart has used the delivery throughout his career. A follow-up album, "The Button-Down Mind Strikes Back", was released six months later and won Best Comedy Performance - Spoken Word that year. Subsequent comedy albums include "Behind the Button-Down Mind of Bob Newhart" (1961), "The Button-Down Mind on TV" (1962), "Bob Newhart Faces Bob Newhart" (1964), "The Windmills Are Weakening" (1965), "This Is It" (1967), "Best of Bob Newhart" (1971), and "Very Funny Bob Newhart" (1973). Years later, he released "Bob Newhart Off the Record" (1992), "The Button-Down Concert" (1997), and "Something Like This" (2001), an anthology of his 1960s Warner Bros. albums.