Ten things

1. It's always Mr. or Mrs. until they tell you different.
2. If you make eye contact, always speak.  Always.
3. Never take a compliment without giving a sincere one back.
4. Say something positive each time you interact.
5. Ask, don't tell.
6. Anticipate, don't react.
7. Listen without trying to justify or defend.  
8. Work on the problem as a we.
9. Every member of your staff should carry a small notepad in their back pocket.  Whenever a member lodges a complaint, makes a request, or gives a compliment, they should be trained to write it down immediately while in the presence of the member.  Get everyone in the habit of doing this and following up quickly. Membership happiness will certainly increase. 
10. Buy 12 thank you cards for each staff member that interacts regularly with the membership, with the goal to write one note of thanks per month.