Is There Really Such a Thing as a FREE Cruise?

We're all familiar with the famous old adage, 'there's no such thing as a free lunch.'  Personal experience has taught most of us to beware offers that appear too good to be true.  That being the well-documented case, is it possible there really could be such a thing as a free cruise? 
The answer, surprisingly, is yes --  and it actually could be easier to score this attractive travel bargain than you might think.  With no timeshare presentation.  No scams.  No $500 'administrative fees.'  No kidding!
The secret to your potential free cruise actually lies in group travel.  Most of the popular cruise lines such as Carnival, Norwegian, Princess, Holland America, and Royal Caribbean offer free berths known as 'tour conductor credits' for groups of 16 or more people traveling together.  Fill 15 berths, and the 16th person usually sails free.  Luxury lines and off-season travel frequently provide TC credits for groups of as few as 10 or 12 travelers.  Note that these numbers are based on double occupancy – while triple and quad occupancy staterooms may be included in the group, only first and second passengers actually count toward fulfilling requirements for tour conductor credits.