To study changes in pain of the back and neck in adolescents between 1985 and 2001 and pain of the neck, shoulder, and lower back between 1991 and 2001. Biennial nationwide postal surveys, 1985-2001, and annual classroom surveys, 1996-2001. Finland. 62 677 12, 14, 16, and 18 year olds and 127 217 14-16 year olds. Pain in the back and neck, neck and shoulder, or lower back, at least weekly. Prevalence of pain in the back and neck was greater in the 1990s than in the 1980s and increased steadily from 1993 to 1997. Pain of the neck and shoulder and pain of the lower back was much more common in 1999 than in 1991 and in 2001 than in 1999. Pain was more common among girls and older groups: pain of the neck and shoulder affected 24% of girls and 12% of boys in 14 year olds, 38% of girls and 16% of boys in 16 year olds, and 45% of girls and 19% of boys in 18 year olds; pain in the lower back affected 8% of girls and 7% of boys in 14 year olds, 14% of girls and 11% of boys in 16 year olds, and 17% of boys and 13% of girls in 18 year olds. Pain in the neck, shoulder, and lower back is becoming more common in Finnish adolescents. This pain suggests a new disease burden of degenerative musculoskeletal disorders in future adults.