Structural Integration is the term developed by Dr. Ida P. Rolf for the systematic reorganization of the myofascial planes of the body to support the dynamic movement and upright posture of the human body in gravity.
Structural Integration is not the same as massage, or myofascial release. Massage releases muscular tension and myofascial release stretches specific areas that have tight myofascial bands. Structural Integration reorganizes the entire human frame through the medium of the myofascial layers. Myofascial sheaths are indeed released, but they are also organized systematically in relationship to their partner layers, which supports their function and stability into the future.
Structural Integration is initially introduced into a person's body in a series of sessions called the Ten Series. Follow up work can be done in the future if needed in single sessions, or three session series. It is possible to do the first session in the series to determine if this form of body work is something that you wish to do.
A more detailed explanation of the myofascial release and organization that makes up the body of work called Structural Integration can be found on this website in the sections called "The Ten Series" and "Does it hurt?". You may also read Dr. Ida. Rolf's detailed text: "Rolfing: The Integration of Human Structures".