Change permission management in Project Online
Project Online offers two security management options for controlling the kind of access that users have to sites and projects:
SharePointPermission Mode With this option selected, a special set of SharePoint security groups are created in sites associated with Project Online. These groups are used to grant users varying levels of access to projects and Project Online functionality.
To learn more about the permissions included in the security groups used with SharePoint Permission Mode, see SharePoint Permissions Mode default permissions for Project Server 2013 SharePoint groups. While this article is written with Project Server 2013 in mind, the information also applies to Project Online.
Project Permission Mode With this option selected, Project Online provides a set of customizable security groups and other functionality that is distinct from SharePoint groups.
Project Online uses SharePoint Permission Mode, by default. This mode is more streamlined, enabling you to implement security quickly and consistently across SharePoint Online and Project Online. However, there may be situations where it makes more sense to use Project Permission Mode. For example, if you think your organization needs to manage access based on the RBS structure, you'll need to use Project Permission Mode. This mode offers greater control, because you can customize and change individual permissions for each security group and typically intended for larger PMO organizations with a requirement to have more granular access control and has in-house expertise (or has engaged with a partner) to help with the implementation.
Site collection administrators have administrative permissions to the Project Online site. These permissions allow the site collection administrator to bypass any Project Online security permissions set in SharePointPermission Mode or Project Permission Mode. This way, someone always has access to Project Online. What should I do if my Project Online administrator gets locked out?
Switching between SharePoint Permission Mode and Project Permission Mode deletes all security-related settings. If you switch from SharePoint Permission Mode to Project Permission Mode, you have to manually configure your security permissions structure in Project Online. Switching from Project Permission Mode back to SharePoint Permission Mode deletes your security permissions information from Project Online.
To change between permission modes:
Go to the the Project Web App site collection as the Project Web App Administrator
On the Project Web App site, click the Settings icon in the top right corner then click PWA Settings
Under the Operational Policies heading, click Additonal Server Settings
In the Permission Management section choose the permission mode that you want and then click Save