Medieval or Renaissance clothing, the costumes worn by participants at SCA events. The term costume is disliked by some participants, as implying something not quite serious.
Many historical recreation or reenactment groups have exacting standards for dress. SCA participants are required to appear at events in their best efforts at historical clothing. This less strict standard results in a very wide range of quality, but also encourages participation at an early stage by members who cannot afford or don't have the knowledge or skills necessary to equip themselves with the best possible kit.
Most members choose to make their own garb, or to hire or persuade friends or colleagues to make it for them. Most local groups have a collection of loaner garb called the gold key. Options for purchasing clothing of good quality are limited - one can't buy a cotehardie at Sears. Providers of suitable clothing are becoming more numerous, however. Resources for researching and making suitable garb are also increasingly available.