Obsession is the last album of what is commonly called the Schenker years in the UFO discography. Michael Schenker enjoyed a relatively short, but intense career for his first stint with UFO. Starting with Phenomenon in 1974 and ending it – from a standpoint of studio album releases – with Obsession in 1978. He for sure put his stamp on UFO and all that stuff they were able to produce in this relatively short time frame. He actually returned to the fold in 1993 for a short time – many years later.