Address Etiquette for "blended" families?

[Edwina's Secretary]

I am a member of a family where the anglo-saxon naming tradition is not often followed. So here are my rules...

Husband and wife with different last names..both first and last names.

Husband and wife with different last names and children..."The Family Jones"...

If I only know one of the spouses well...to the spouse I know.

If I do not know them well enough to know how I should address them...do I know them well enough to send a card????

[Catty1]

This is a realtor's database - some are clients and some are friends(most are clients! )

Thank you all for the input. Gives me some common sense to go by!

[Twisterdog]

I just did my Christmas cards, so this is actually fresh in my mind.

I don't put any kids' names on the envelopes, only the adults.

If everyone has the same last name I put "The Smith Family" if they have kids at home or "John and Jane Smith" if they don't.

If they have different last names I put "John Smith and Jane Jones".