Focus were a Dutch band led by guitarist Jan Akkerman that debuted with In And Out Of Focus (1970).

Moving Waves (1972) contains the fast-paced novelty number Hocus Pocus, a melodic fantasy for the age of hard-rock. But the album's centerpiece is actually the 23-minute jam Eruption, their equivalent of the Colosseum's Valentyne Suite.

Following albums were far less interesting: Focus 3 (1972), that contains the 27-minute instrumental jam Anonymus II (way too long for what it has to say), Hamburger Concerto (1974), that contains the ambitious (and much better) side-long title-track, Ship Of Memories (1974), Mother Focus (1975).

In 1977 Belgian jazz guitarist Philip Catherine replaced Akkerman and Focus releases Focus Con Proby (1978).