A big project has its own SharePoint site to enhance communication between stakeholders. The PMO of the project maintains it. SharePoint is a great tool; However, the maintenance of the user access is very difficult if you have more than 50 users/stakeholders.
This is the reason I have created the following tool to maintain the users on a SharePoint site. It really saves time and gives a much better oversight than the Web Interface. The file itself contains help.
Download: SharepointMaintainGroupTool