If you, as a freelancer, book times for a cooperation project for which the approval process is active, you can only bill the times after they have been approved. You can submit a 'timesheet' at any time to request approval. You will be informed of the status change by e-mail and can bill your times as soon as the times have been approved.
The approval process can optionally be activated per user and project. You decide which of your employees need to go through the approval process and which don't.
A customer can optionally be stored as an approver. Once times are approved on a timesheet, they are immutable and can be billed.
Depending on the configuration, freelancers automatically receive a credit for the hours they have worked after the timesheet has been released. Optionally, the hours can also be automatically imported into the customer's SAP system after they have been released.