If you have several translation memory files and wish to join them into one big translation memory,

1. Place all the memory files into one folder.
2. Check "Memories folder" box in Translation Memories (TMX) panel on the Dashboard.
3. Click "Add memory" button in Translation Memories (TMX) panel and select the folder with translation memory files.
4. After choosing the folder, its name will appear in the Dashboard > Translation Memories (TMX) panel.
5. Open or create a new project.
6. Alternatively, you can select a folder with translation memories in the main interface via Memory > Open memories folder... menu. The Memory menu can be activated via View > Show memory menu.
7. Joined translation memories will load as one TM.
8. You can save all the segments from joined memories into one translation memory (TMX) file. Click the tab with the joined memories and choose the menu Memory > Save memory as... .