A runway model will need to maintain the appearance he or she had when she signed on to the agency. This means maintaining a certain weight and body type; as it is well known, most models are quite thin, though there are a number of plus-size models that now work on the runways as well. Most models also need to be very tall and have a certain narrow body type, so that all of the sample clothes created by the designers will fit them without any adjustments needed.