Design assurance is a system of the design process support,  i.e. a set of documented actions that ensure that the output of the design process is  exactly the product that you want to design.

This is especially important for products for which it is very difficult to choose any quantitative evaluation criteria or there are so many of them that it is impossible to evaluate them all, and it is difficult to classify them according to the degree of importance. Therefore, such a system is relevant for the aviation and space industry, whose products have the following features:

- long design life;

- correctness of the put technical decisions can be estimated as a result of full-scale tests at the final stage of design;

- high resource requirements (for the aviation industry) and absolute reliability (spacecraft);

— there are not only quantitative, but also qualitative criteria for product perfection.

The main thing in the system is to arrange the necessary personnel, endowed with certain qualities and having the necessary means, so that using the necessary organizational structure and the necessary methods to minimize the risks of the design program. The system does not require large financial investments, its main meaning is to properly use the available resources. It is very important to apply the system in the initial phases of the project, as the result of all other work will depend on it.

The design guarantee system can be compared to an automatic transmission in the car, which not only relieves the load from the driver, but also reduces the requirements for his qualification and allows for high reliability of control while reducing the loads on the transmission of the car. Such a system is very important for complex and highly integrated systems, for example, on the aircraft there are mechanical systems, and there are digital ones. In the first case it is possible to manage quantitative indicators of work and on them to estimate perfection of system, in the second case some qualitative criteria of an assessment are necessary. If there is also an interface between such systems, the risk of incorrect design, and most importantly, the wrong understanding that the product is no good, increases significantly. After all, in this case, the dominant role"  is played by who, where, when and with what?" criteria, rather than  " what and how much?"

Implementation of the design assurance system provides the following advantages:

Performing of the system procedures ensures that all necessary product requirements are defined;

Identification of all deviations from the specified parameters at the earliest stages of the project;

By controlling the system, you can control the correctness of the design process;

The implementation of the system significantly releases the management from the current supervision of the design and allows you to focus on promising issues, i.e. to engage in strategy rather than tactics. The design assurance system is also important when the design has already been completed.

After all, with the beginning of serial production, the design process is not over, new problems appear –  changes in the product type design, classification and deviations management, a common understanding of these issues in the spaced production of products and close interaction between all participants in this process.

Such a system cannot be supplanted by a system of quality – because the quality system is important to ensure the sameness of all serial copies between them and their compliance with the designed and tested model, and the main task of design assurance system  is the alignment of the designed sample with initial requirements, i.e. "got what you wanted."