When you have multiple projects, and as your reference database grows, organize references in Groups, Group Sets, and Smart Groups in order to navigate among and find references easily. It is a good idea to keep a single EndNote library and within that library organize references in groups.
Create Group Sets: References are organized in Groups, and groups are organized in Group Sets. You can move Group Sets up or down. Make your current project Group Set at the top of the Groups panel, on the left side of the page.
Create Smart Groups: Smart groups are created by searching your EndNote library. From the Groups menu, chose Smart Groups. A search box will appear. Select search parameters you wanted in the results.
Create From Groups creates a group by searching multiple Groups at the same time for creating a combination group.
Image above shows 1. Groups panel (My Groups), 2. Group set, 3. Group, 4. Smart Group.
EndNote Library Window image below shows 1. Groups panel 2. Reference display 3. Search EndNote references 4. Reference Abstract 5. Reference Summary 6. PDF viewer 7. Copy Reference