Few people on any side of the industry, least of all the Contractor’s quantity surveyor, appreciate the true extent of the staff and supervision costs incurred by you, the Specialist Subcontractor, in the implementation of variation instructions. I am not referring here to the more obvious costs of installation and commissioning, but to the associated ‘preliminaries’ and oncosts. In fact, standard subcontract conditions often provide for such elements to be evaluated and included in the agreed valuation, if appropriate. It is up to you to bring these matters to the fore, and to ‘educate’ the other parties, if necessary, in order that you get properly paid for the true costs of carrying out the variation.