The purpose of this article is to present the suitable location of portals during knee arthroscopy in various situations. It includes universal portal, meniscal lesions, discoid meniscus, 1-incision technique of posterior and of anterior cruciate ligament reconstructions, stiff knee, transseptal posterior portal, and far midpatellar portal. These specific descriptions in each situation are drawn from the accumulated experience of more than 4,000 cases of arthroscopy. Our philosophy on the positioning of knee portals can be emphasized from 2 perspectives: first, the location of portals should flexibly suit the surgeon's need rather than a fixed location; second, the higher the portal position is in knee arthroscopy, the wider view it generally provides inside the joint.