The Organize tab lets you create and manage groups, share groups with others, find any duplicates among your references and manage attachments such as PDF files.
If you want to share a group with others, for example, your thesis writing partners, tick the box in front of Manage Sharing. You will see that a collaboration icon is displayed in front of the name of the group:
University library Jönköping University campus, building C Gjuterigatan 5 553 18 Jönköping