A quantity surveyor is responsible for controlling the costs of building work, by measurement and valuation. In the uk, there are two kinds of quantity surveyor, the professional q.s. who is engaged right from the beginning of a contract, advising the architect of probable costs during the design process, then the preparation of documents to enable various building contractors to submit tenders for the proposed work, and then financial control as the work proceeds, right through to the preparation of a final account that would include any additional work caused by variations to the original design. Then there is the contractors q.s. who is concerned with ensuring that his employer is properly recompensed as the work proceeds, and who negotiates with the professional q.s. on all financial issues that arise during the progress of the work. I retired 20 years ago, so I imagine that the computer is more involved with the process now. These days the quantity surveyor is also involved in project management.