I definitely recommend a lanyard. I use a clip type device sold in fly fishing stores that allows me to unhook the knife from the lanyard, which is attached to my belt. I put a small loop of rope through the lanyard hole, attach the clip to the loop and tie the lanyard to my belt. This has saved me more than once, especially when I'm wearing lightweight nylon pants, which are very "slippery." My pocket knife wants to slide out of the pocket when I'm sitting in my canoe, for instance.
------------------
Hoodoo
I get some pleasure from finding a relentlessly peaceful use for a combative looking knife.
JKM