To be effective, whistleblowing policies should be adapted to the organisational culture. They need to be custom-made and not follow a one-size-fits-all logic, specifically when they are installed to stimulate responsible peer reporting, a highly sensitive and value-laden type of whistleblowing. This paper attempts to illustrate that grid-group cultural theory could help to construct a whistleblowing policy by linking reporting styles to the organisational culture. First, we will identify four types of policy measures that are hypothesized to be effective in (...) four types of organisational culture. Second, we develop the hypothesis that certain organisational cultures can induce peer reporting that is harmful for the organisation. The whistleblowing policy can then be used as a catalyst for cultural change. (shrink)