The thesis is focused on marketing research using methods Mystery of activity in the sphere of consumer cooperatives. It outlines the development of consumer co-operatives in the Czech Republic and the historical origins of the development, from the camp. The practical part is realized in business units Unity from the camp, specifically in the stores included in the retail chain COOP TIP. Marketing research has focused on determining the level of service and quality of supply of goods. The analyzed information was the basis for the comparison of results obtained from the research of individual stores and to formulate measures to increase the effectiveness of marketing activities, consumer cooperatives Jednota, from the camp.