Many of us carry a knife, just because. Some carry for mundane chores, others for use as a life saving tool. Based off many years of experience, these two things should not be combined, even though they can be. If you carry one to open boxes, cut seatbelts, or anything other than defense; it should be left as that. If it is for defense, then it should be strictly relegated to this task. Defense, or back up to the primary sidearm, is what this article will concentrate on.

What is the purpose of the defensive knife? Is it in case you lose your primary sidearm, or it malfunctions in close quarters when a murderous attacker is on top of you? Is it to aid in retaining your primary sidearm? Is it quicker to access in a tight space then your sidearm? Your individual mission is what will determine which kind of knife is best.

It is no secret that a fixed blade knife is the quickest into action. However, everything is a compromise. Carrying a fixed blade knife, that is visible, offers an expedient weapon immediately available to everyone around you, as most knife sheaths do not have active retention on them. If you do choose to carry a fixed blade knife (even if it is “concealed” behind your magazine pouch), be aware that it can be used against you, and there have been documented cases of this happening.

Probably the most popular choice for this type of knife with law enforcement is the TDI knife line by Ka-Bar. Fortunately, there are some of these models that do have a type of retention on the sheath, so that is a step in the right direction. However, can you draw it with either hand? Is it comfortable, and will you wear it regularly?

Do not discount the speed, agility, robustness, and the advantages of the fixed blade knife. They can easily be concealed in pant pocket, a trauma pouch, in a neck sheath, or behind an overt vest, even in an ankle rig. They have their place, and it just takes a little bit of thinking to see what fits you best in your circumstance.

The other knife that we are going to look at is the folder. Again, can you get to it with either hand? Can you open it with gloves on, if your hands are wet or bloody, if your hands are cold? The easiest folder to open has a large thumb HOLE in the blade. The most prolific is Spyderco, though some other companies (such as Benchmade) have the blade hole opener. The hole is much easier to open under austere conditions than is a disc.

About twenty years ago, an invention came on the market called the “wave.” It catches on the edge of the pocket when the knife is drawn to open the blade without having to use the thumb. It looks good, and it works good, when there is no pressure on the user. When you are in close quarters, and under duress, it tends not to open fully, or at all. It is not something you really want to rely on when your life is at stake.

One type of defensive knife you should avoid is the automatic. Be it one that you push a button on and it opens out the side, or one that has a slider that shoots the blade out the front. These look really cool, but often don’t work so well when they are under lubricated, have common pocket debris caught in the tracks, or come in contact with any kind of mild barrier. Once they fail to open, it is harder to get them into action than a folder. The buttons are also harder to activate than a large, robust thumb hole.

Serrations on knives have the advantage of not having to be as sharp as a straight edge to still cut well. They have the disadvantage of getting caught up in leather, and other thick garments. Everything is a trade off. Do you work in a tropical climate for most of the year, or one with harsh winters?

What it comes down to is what you are willing to carry, routinely. Most everything comes down to convenience. Human nature is to follow the path of least resistance. No matter how cool something is, or how effective it is, most people will not carry it if it is too heavy, or bulky, or uncomfortable.

As to what I would recommend, there are a handful of makes and models that have proven themselves over the years in pressure testing, and have an actual basis or design as reliable defensive tools.

Spyderco: Delica, Civilian, Matriarch, Canis, Street Beat, Street Bowie, Endura, ARK, and a whole host of others.

Shivworks: Clinch Pick and Disciple.

Fred Perrin: Multiple designs.

Joe Watson: HITS line.

Ka-Bar: TDI line.

While there are many others, you can’t go wrong with the proven designs above. Pay your money, take your chances. Critically think through your situation, and what options you have. Once you have decided on the knife or knives, get training, and practice. Then practice some more. Then just a little more.