Background: Intermediaries are an inherent part of global trade that take over various tasks within supply chains. These supply chain facilitators play vital roles within the trade of goods and services and over time, they have evolved into different types. These types have been categorized with regards to various factors, but within this study, the factors involvement and power are examined. Purpose: The purpose of this study is to develop a categorization of intermediaries within the companies’ supply chains. In addition, a categorization technique is aligned. This is important as most models established in the literature do not show steps of assessments. A black box is created, which hides processes and steps for outsiders. In addition, literature does show categorizations of intermediaries, however, no categorizations with involvement and power exist. Since some literature states that some intermediaries are very powerful within supply chain relationships, the purpose is to examine these relationships with regard to involvement and power. Method: This study is a multiple case study of a qualitative character. Semi-structured interviews are conducted in order to collect data. The data is processed via a qualitative content analysis. First, the collected data is quoted, in a second step it is coded, categorized and then explained and finally interpreted. In order to establish a categorization model, a technique to assess the categorization is developed by the authors themselves. Conclusion: The results show that intermediaries are involved within supply chains on a medium to high level. Intermediaries contain power on a low to medium level within supply chains. The technique that is established in order to receive results with regards to involvement and power, contains of 11 steps that range from choosing factors to the results and also includes the specific steps that usually are hidden in the black box.