Reflexology is a spa treatment where the therapist works on "reflex points" on your feet, hands, and head (especially ears). The theory behind reflexology is that these reflex points relate to specific organs and glands in the body, and stimulating those points with finger pressure promotes health in those organs and glands via the body's energetic pathways.
When done by a skilled practitioner, reflexology is a deeply relaxing treatment with benefits that can be felt throughout the body. The therapist will use various techniques that include holds, finger pressure, kneading, rotation and rubbing.
The best therapists also include hands and feet as part of the reflexology treatment, and you should feel an effect through the entire body.