Reference: Worf in ST:TNG Episode - *Ethics*

The history of the qutluch

"The qutluch - blade of the Assassin - is smaller than the d'k tagh but has considerably more killing power when used correctly.  Klingons look at death in a totally different manner than do Humans -death for a Klingon is merely a transition from one battle ground to the next.  HOW one dies is what is important to a Klingon. Equally important is how a warrior kills his enemy.  As always honor is paramount - the code of honor that is strictly outlined in Klingon history stretching from the time of Kahless when he used honor as the building blocks for a Galactic
Empire.

    Assassination is considered an honorable death as well as an honorable profession if it is carried out according to ancient guidelines. The primary aspect of assassination is that the two parties MUST fight face to face.  To look into your victims eyes at the moment of death is the way of the warrior. Stabbing in the back or from the shadows or the use of modern or chemical weapons is strictly against the code of honor.  Secondly, assassination should be carried out with weapons of ancient design - clubs, cudgels and knives are the weapons most often chosen.

    When looking at the qutluch you can draw your own conclusions as to its development. It is a weapon designed to breach any armor and produce maximum destruction of internal organs . The weapon produces a very characteristic wound of savage brutality. When Kurn was attacked by this blade, Worf could identify the *tool* by the wound itself.  And finally assassination should be carried out quickly and efficiently. If the assassin does not carry out his work quickly, he might find himself on the wrong end of the blade. The qutluch design makes this aspect a
reality in the hands of the trained assassin. The razor tip creates quick access and the saw-teeth sever arteries on the knife's path in and out.  Every aspect of the blade is designed to produce maximum damage and the formed handle provides a sure grip in all situations.   I make sure mine is always sharp. "

                                                                -GuildMaster K'daq of the KIWG

"This can be a nasty weapon in trained hands.  I remember a time when no Klingon would stab another in the back, use a Romulan HoHwI' or even dare use poison. Unfortunately these days there are too many Klingons who would use such methods.  A trained House Assassin can be silent, cunning, and deadly... But should he stray from the Warrior's Code he will not only have one blood oath on his head but TWO.  One from the family whose member he has killed, and one from the family that hired him."