KRS-One (aka Lawrence Parker) was the sole constant member of Boogie Down Productions, whose 1987 album, Criminal Minded, is often cited as the record that introduced gangsta rap to an unsuspecting world. But BDP's raps were always as literate as they were gritty, and the act quickly evolved beyond its street-level journalism, producing lyrics that spelled out political and social ills on a wider scale. The song "Beef," from the 1990 album Edutainment, must have seemed bizarre, championing vegetarianism at such an early date. But KRS-One has always been a bit ahead of the curve, and to this day remains a controversial figure not only for his music, but also for his outspoken public persona. The recently released Back to the L.A.B. is among his finest.