Perceptions of stakeholders can influence who is included and excluded from environmental policy-making processes. Repertory grid technique is a qualitative method that captures how a person differentiates objects according to dimensions of similarity. Used in a qualitative way, repertory grids reflect a person's individual constructed reality of the world. We adapt the technique to create a quantitative perception matrix that offers research participants the same set of stakeholder groups and descriptors that, unlike qualitative applications, can be used to compare perceptions between decision-makers to understand and predict preferences for stakeholder inclusion. Eight senior policy advisors and six scientists who were involved in developing fox eradication policies in Tasmania, Australia, completed a perception matrix with a supplied set of stakeholder groups (i.e. repertory grid elements, e.g. government, media, general community) and descriptors (i.e. repertory grid constructs, e.g. credibility, effectiveness, influence). They rated each stakeholder group against each descriptor. The results show that different groups of stakeholders were rated similarly to each other, for example, scientific experts and government departments were rated similarly between participants, and were considered more credible and effective than the general community and the media. The results also show that sets of descriptors were used to describe stakeholders, for instance if a stakeholder was perceived to be credible, they also tended to be perceived as effective. Differences between policy advisors and scientists revealed opportunities to explore functional roles of stakeholders, where stakeholders are considered in terms of what they can offer to the decision making process, rather than who they are. Our adaptation of repertory grid technique, with supplied elements and constructs, demonstrates the usefulness of perception matrices in enabling statistical comparison of implicit perceptions; identifying similarity and variability among individuals’ perceptions of stakeholders; and providing a visual representation of the structure of perceptions of groups of individuals.