You can share your Google contacts to other Google accounts. This feature is especially useful for groups who have same clientele. (Ie. Helpdesk) Note, that you can only share all of the contacts. You can't share contacts one group at a time. To share single group, you can send it as a CSV file.
Sharing all contacts to other user
1. Open contacts --> https://www.google.com/contacts/
2. Select More --> Manage delegation settings
3. On the sharing area, write the users you want to share the contacts with. You can write a message that will be included also.
4. Click Share & save
5. Your contacts will be now visible for the users you have shared them with. They will be shown under Delegated contacts section.
Note! You can share the contacts with or without editing rights.