Commonly during construction occur some issues when contractor, or supervision, can’t find an adequate solution. The most commonly, that issue is a certain change in design assumptions that has occurred during the construction and was not known at the time of project development and designing. In such case it is an obligation to contact the designer to provide appropriate interpretation of construction project or some parts of it. Services of Design supervision include interpretation of technical elements from project if it is required at construction site or if it is requested by supervision engineer. Design supervision approve some changes in blueprints or some exceptions in design and technical solutions, and also as interpretation of quality control results.