The aim is to describe how to build a foundation of resources in RBSUs by addressing the issues of access to and control on resources in order to understand this context and to further develop the language of RBSUs. The research lies in the interpretative field of inquiry. Abduction is used to combine empirical data with theoretical studies in order to try to investigate patterns that could give an understanding of the phenomena that is studied. Descriptive research approach using multiple-case study design is used. The first part of the theoretical frame of references explores existing theories on resources. This leads to RBSUs basic resources. The second part explores different means for accessing and controlling resources. The chosen approach is qualitative. Interviews have been conducted for data collection. Documents are gathered and analyzed to support the interviews. Following each stage of RBSUs development, it is described what resources are the most important ones to each RBSU and how they got access to and control over those resources. The major contribution is that RBSUs access and control their basic resources in different ways depending on the stage of the RBSU development. In addition, the findings describe and allow understanding how RBSUs‟ founders make their choices when it comes to build a foundation of resources in each of those stages.