This paper focusses on JET's contribution through experimental and com
putational studies to solving the ITER divertor problem. Results from
detached plasmas in the ''Old'' JET configuration of 1991 and the new
JET pumped divertor of 1994 are presented and compared with numerical
simulations based on the EDGE2D/NIMBUS suite of codes. A computational
study of detached plasmas is undertaken in the context of the differe
nt divertor configurations planned in the JET programme.