Now that the partnership (well in part ownership by LH) of Brussels Airlines and Lufthansa is completed, both airlines frequent flyer programs are offering double miles for flying on the other airlines’ flights.
For Brussels Airlines Privileges members, double miles can be earned on the first two flights taken with Lufthansa and/or SWISS.
For Miles and More Members, double miles can be earned on the first two flights taken with Brussels Airlines.
Both offers run Mar 29 – Jun 30, 09 and the Miles and More offer requires registration.
For Brussels Privileges members see the details here
For Miles and More members see the details and register here
And if you are a member of both programs register for both and try to maximize your miles!