Background/Context: The data team intervention was designed to support schools in using data while developing a solution to an educational problem. The participating data team members are responsible for building collective capacity within their school for using data and implementing actions related to the improvement plan. This can be challenging, because although they have gained knowledge and experience with data use and the educational problem, their colleagues who were not on the data team have not. As a result, there is a heightened risk for discontinuity between the behaviors of such colleagues and of the data team members: Colleagues will not automatically use data nor implement the actions for improvement. These discontinuities are referred to as boundaries. To establish common ground with their colleagues, data team members need to act as boundary crossers by brokering their knowledge. Purpose: The present study used a process view to determine how data team members acted as boundary crossers by studying what content they had brokered, the level at which they had addressed that content, and what activities they had used to cross boundaries. Intervention: Data teams consist of six to eight educators who collaboratively learn how to use data to analyze and address an educational problem at their school. They work following a cyclical procedure. Research Design: A longitudinal qualitative case study was conducted in four Dutch schools that implemented the data team intervention. Data Collection and Analysis: Artifacts were collected and all team members were interviewed twice. Log files, minutes of the meetings, and progress reports were used to obtain a complete picture of boundary crossing and to provide background information. A coding scheme was used in order to determine what content was brokered, the level at which the content was addressed, and the activities used to broker the content. Findings/Results: Findings illustrated that team members mainly brokered knowledge about the educational problem and data use as applied to the educational problem, but rarely about data use in general. Overall, content was almost exclusively addressed at the level of awareness, indicating that only basic information was brokered. Conclusions/Recommendations: Successful boundary crossing cannot be taken for granted: Team members brokered their knowledge in ways less likely to be effective. When they receive additional support for this, they are likely to increase their team's effectiveness in building school-wide capacity for both data use and the implementation of actions related to the improvement plan.