If you need to send details for a case to another user, for read only purposes, you can use the Notify Other User feature. Note that you can only use this feature with other users in your organization, and only users in your organization who have an email address associated with their profile.
You can share case details or limit the share specifically to a billing report or case summary.
To notify another user:
Step 1: With a case selected, click on the Notify Other User link in the preview pane.

The Notify Other User window opens.

The providers listed are local providers with your organization that have an email address associated with their profile.
Step 2: Select the provider to notify by clicking on his/her name. The second Notify Other User window opens.

Step 3: Select the information to share, add any additional information in the Comments field, and click on the Send button. The provider will receive an email notification with a link to the specific information you have shared.