how to synchronize my Gmail contacts with iCloud contacts on iPad/iPhone/McBook

I use Gmail to organize my contacts and could copy them to my contact-book from iPad/iPhone/McBook.

The contacts from the iPad/iPone/McBook are synchronized my iCloud, but unless I say iCloud had to use my Gmail account, the contacts from Gmail are not synchronized with iCloud.

So if I change contacts in my iPhone, I have to change them manually in Gmail and visa versa.

At the new Geniusbar in Amsterdam they could not help me, so maybe somebody here know the solution.

Thanks a lot.

Remko