Research of this kind depends on the researcher putting herself in the role of the shopper and on assessment of service at the evaluated point. This is used above all in situations where it is necessary to diagnose the level of the service offered to the shoppers individually, for example, in banks, at retail outlets, and at customer service points. It is also used to assess relationships with business clients, as well as sometimes through public institutions for assessing the level of client service in public offices.

The research generally begins with the development of the evaluation questionnaire, which is a reflection of the service standards implemented or desired by the company or institution. Such a questionnaire is filled out by the "mystery shopper" during his visit or meeting with the sales or service person. For example, the researcher as a "mystery shopper" goes to an automobile dealership, behaves according to the established visit script and, after the visit, fills out the detailed questionnaire and notes down his observations.

The research may be of a wider or a narrower nature, and may concern only the observations of a few aspects of the service (sign markings for the service point, the number of consultants, the speed of reaction, the look of the sales point), or it may lead to an actual sale of products or to actual service. It may concern the assessment of these places or of the competition. Finally, it may be conducted in the form of observation, personal visits, and interaction with service, either by telephone or via the internet.