Calendar Sharing controls the ability for a user to see another user's Calendar ( and other ) data. Calendar Sharing is One Directional, meaning that if you set up to have User A shares his/her calendar with User B, it does not mean that User B will automatically share his/her data with User A. You can have one way, or two way sharing.

In addition to Calendar data, Calls, Cases, Quotes, Timesheets, Expenses, Bugs, Calendar Tasks and Project Tasks are also controlled by Calendar Sharing. In other words, when you browse the summary page of these entities, the view by user drop down are controlled by Calendar Sharing, and only shows those users who share their data with you.

While individual user can choose whom to share his/her data with, Calendar Sharing are best configured by administrators. There are two ways to configure this: Between Two People, and/or From a User Group. Please see the next two Q/A for each setup.

Navigate to Calendar -> Settings page, [Sharing] tab, and click on the link "Setup access sharing between users ( Admin Only )". Here you can choose any two users, and specify the sharing between the two. ( One direction or both direction ).

Navigate to Calendar -> Settings page, [Sharing] tab, and click on the link "Setup Access Sharing - User Groups ( Admin Only )". If you do not already have a user group, you can create a new group, and include all the relevant users in the group. Once you have included all relevant users, click on the "Access Sharing" link for that user group, to configure who can access whose data.

A common question from our customers goes something like this: "I have already included User A and User B in the same user group. Why can they not see each other's calendar data?" And the reason is that just by having users in the same group does not mean their calendar data is shared. Having them in the same group just gave you an easy way to configure the sharing between them, but does not automatically imply sharing in any way.