He became interested in folk and rock music in his teens and in 1965 began performing under the name Steve Adams. Mike Hurst, a former member of the folk-pop group the Springfields, who had become a record producer, heard him and took him into a recording studio to cut his composition "I Love My Dog." This demo caused Decca Records to sign him under the name Cat Stevens and assign him to its newly formed Deram subsidiary. "I Love My Dog" reached the British charts in October 1966, peaking in the Top 40.

Stevens' next single, "Matthew & Son," entered the charts in January 1967 and just missed getting to number one. It was another self-written effort, and Stevens' reputation as a writer was further enhanced by the success of his song "Here Comes My Baby," which was recorded by the Tremeloes and entered the British charts in February, reaching the Top Five. Stevens' third single, "I'm Gonna Get Me a Gun," entered the British charts in March and reached the Top Ten, preceded by his debut album, Matthew & Son, also a Top Ten entry.

In May, P.P. Arnold got into the British charts with Stevens' composition "The First Cut Is the Deepest," peaking in the Top 20. Stevens' fourth single, "A Bad Night," was in the charts in August, peaking in the Top 20. That was a disappointment, considering his recent success, and his next records did even worse: "Kitty," his fifth single, barely made the charts in December, while "New Masters", his second album, didn't chart at all. Even worse, in March 1968, Stevens contracted tuberculosis and was hospitalized for three months. He spent a year recuperating. After the failure of an intended comeback single, "Where Are You," released in July 1969, he parted ways with Deram.

Stevens began writing more personal, introspective material and signed a new contract with Island Records. A third album, Mona Bone Jakon, came in April 1970. From the album, the single "Lady D'Arbanville" was issued in June 1970 and became his third Top Ten hit in the U.K. Stevens' talent as a songwriter for others had not deserted him; in August, Jimmy Cliff entered the British charts with his composition "Wild World," reaching the Top Ten. With a backlog of material, Stevens had a second Island album, Tea for the Tillerman, out in November; it made the U.K. Top 20. With that, Stevens suddenly became a major star in the U.S. Tea for the Tillerman reached the Top Ten and went gold; Mona Bone Jakon finally reached the charts. Stevens was hailed as one of the most important figures in the currently popular folk-rock singer/songwriter trend, along with James Taylor, Carole King, and others.

In June 1971, Stevens released a new single, "Moon Shadow," which made the Top 40 in the U.S. and the U.K. This was followed in September by "Peace Train," which hit the pop Top Five and reached number one in the easy listening charts in the U.S., just in advance of Stevens' fifth album, Teaser and the Firecat. An immediate gold-record seller, the LP just missed the top of the U.S. charts and hit the Top Five in the U.K. In addition to "Moon Shadow" and "Peace Train," it contained "Morning Has Broken," an adaptation of a hymn, which became Stevens' second consecutive easy listening number one and reached the pop Top Ten on both sides of the Atlantic.

Catch Bull at Four; a slightly harder-rocking effort, was released in October 1972 and represented Stevens' commercial peak: it hit number one in the U.S., earning gold-record status immediately. Different singles from the album were released in the two countries, in the U.S. "Sitting" and in the U.K. "Can't Keep It In"; both reached the Top 20.

By 1973, Stevens was again beginning to show signs of the strain of being a pop star, even if he didn't become physically ill. He released a new single, "The Hurt," which made the U.S. Top 40. It was followed in August by his seventh album, Foreigner, an ambitious effort that featured an entire LP side given over to a musical suite. The record was another massive commercial success, peaking inside the Top Five in the U.S. and U.K. and going gold instantly.

Stevens issued his eighth album, Buddha and the Chocolate Box, in March 1974, preceded by the single "Oh Very Young," a Top Ten hit. As usual, the album made the U.S. and U.K. Top Five and went gold upon release. In July, Stevens released an independent summer single, a revival of Sam Cooke's "Another Saturday Night," and it made the U.S. Top Ten and the U.K. Top 20. In November, A&M extracted "Ready" from Buddha and the Chocolate Box and released it as a single that made the Top 40. Stevens' Greatest Hits LP was released in June 1975 and predictably was a big success, eventually selling over three million copies in the U.S. alone. "Two Fine People," a new song featured on it, reached the American Top 40.

Stevens had his ninth regular album release, Numbers out in November, but this album only made the Top 20 in the U.S. Though it was certified gold within a couple of months, did not generate a Top 40 single, and missed the charts entirely in the U.K. Stevens took 18 months to deliver his tenth album, Izitso, in May 1977. It restored some of his commercial clout, hitting the U.S. Top Ten and being certified gold in a month, while reaching the U.K. Top 20, and the single "Old School Yard" made the Top 40 in America and charted in Great Britain.

In 1977, Stevens formally became a Muslim and adopted the name Yusuf Islam. Notwithstanding this change, there was an 11th and final Cat Stevens album, Back to Earth, released in December 1978; it sold modestly. With that, Yusuf Islam retired from the pop music business.
source: All Music Guide