Original: In 1986 the West Midlands County Council was abolished and Birmingham, Coventry, and Solihull became effective unitary authorities, however the West Midlands county name has not been altogether abolished, and still exists for ceremonial purposes, and so these cities still remain outside Warwickshire.
Simplified: Since 1986 Birmingham, Coventry, and Solihull have been effective unitary authorities, but they still remain legally part of the West Midlands.