Although there are a lot of ways that you can defend against a knife, every technique is based on the same principle. These are: 1. Be in control. This involves assessing whether it is worth the risk of confronting a knife or not and if yes, maintaining enough control of the knife to not let it stick in you. On your part it will take strength, tehnique, and obviously smarts. 2. Accept losses.. It is the unfortuante thruth that in knife fights it is very likely that you will get hurt in some way. However, should you know your stuff, you can at least control where and how you are hurt. When already engaged in a knife encounter, remember that you lose much of any control when you run.