A stakeholder matrix is a tool used to identify, analyze, and prioritize stakeholders based on their level of interest or influence in a project or business. It is used to help manage relationships with stakeholders, ensure that their needs and concerns are addressed, and to help make decisions that align with the overall goals of the project or business.
 
Once you have identified and assessed the stakeholders, you can use the matrix to help determine how to best communicate and engage each stakeholder.  Stakeholders with high levels of interest or influence may require more frequent or detailed communication, while those with lower levels may only need occasional updates.