It is based on the principle that there are reflexes in the feet which correspond to every part of the body. Reflexology serves to relax, improve circulation and promote a general feeling of wellness.
Reflexology is different than massage. It is thought that reflexology works through nerve endings whereas massage is applied to the muscles and soft tissue of the body.
A treatment should not be painful, though there may be uncomfortable or tender areas if your body is highly stressed. The more one applies pressure to those areas, the less tender they will become.