People practice Scientology by moving up the "Grade Chart," officially known as the "Classification Gradation and Awareness Chart of Levels and Certificates." It outlines a series of steps one must take in sequence to reach the highest levels of awareness. The progression also is referred to as "the Bridge," short for "the Bridge to Total Freedom."Parishioners move up two sides of the Bridge. On one side they receive counseling called "auditing" from "auditors," who ask questions of a person while measuring his emotional reactions using an electronic device called an "e-meter." On the other side of the Bridge, Scientologists learn how to become auditors.At the top of the bridge are the "Operating Thetan" or OT levels. In Scientology, an OT is a being who no longer is dependent on his body or the physical world around him and is fully aware of his immortality as he passes through an endless succession of lifetimes in other bodies. Reaching the highest level — OT VIII — usually requires a Scientologist to spend years and tens of thousands of dollars on courses, counseling, books, lectures and other materials.Though often criticized for charging for its services, Scientology says the nature of its counseling demands that people pay for it. The church explains that it takes a team of staffers to deliver counseling to each Scientologist, in contrast to denominations where one pastor, priest or rabbi can minister to hundreds. To climb the Bridge, Scientologists start with introductory services and work their way up. Some highlights, from the bottom up: OT levels: No longer limited by his "reactive mind," the parishioner who becomes "clear" is ready for the next level of abilities — that of the OT. According to the church, an OT can operate independently of his body. "He's now himself, he's not dependent on the universe around him." Scientologists in these levels often speak of having the ability to control their lives completely and being able to "go exterior" of their bodies. There are 15 OT levels listed on the bridge chart, but the church currently offers only eight levels. Reaching the first six levels can cost $60,000 or more. Reaching levels seven and eight can cost tens of thousands of dollars more, depending on the pace of a person's counseling progress. Preparations for OT: Courses and advanced counseling sessions that prepare people for the OT levels, which compose the upper echelons of Scientology. Parishioners are taught the skill of auditing themselves. They also undergo "security checks" to ensure they can be trusted not to divulge OT specifics to others. The total costs for these preparations can be in the $20,000 range. Clear: A Scientologist reaches this state when he has worked his way through the grades and New Era Dianetics and is said to be permanently freed from his "reactive mind." According to Hubbard, the reactive mind is the part of the mind that stores "engrams" or images of past traumas that can cause fears, pain and psychosomatic illnesses. The church says, "Clears are self-confident, happy and generally successful in both careers and interpersonal relationships." The grades and New Era Dianetics: Counseling sessions that parishioners must progress through to reach the state of "Clear." Scientologists say the sessions help "rehabilitate or strengthen specific spiritual abilities" such as solving problems, repairing relationships and addressing personal traumas, including fear of heights or public speaking. Multiple sessions, which probe a person's past through prescribed lists of questions, can total as much as $40,000 to $60,000. Training routines and objective processing: Courses and drills that ready a person for further auditing. The church says they teach people to concentrate on the present, communicate better and be in control. Purification Rundown: The church says people must undergo the "Purif" before lasting spiritual gains can occur. It's a detoxification program of exercise, vitamins, nutrition and sauna use. Scientologists say it rids the body of drug residues and other toxins by dislodging them from fatty tissues. The process lasts five hours a day for two to four weeks. The cost can vary. Most reported costs are in the $1,500 to $2,500 range. Introductory services: Courses, books, films, CDs and introductory auditing that offer a grounding in Scientology. Parishioners become familiar with Dianetics: The Modern Science of Mental Health, the 1950 book by the late Scientology founder L. Ron Hubbard. They can listen to recorded Hubbard lectures, take a personality test, a communication course or a "life improvement" course on subjects such as how to be a better parent. Costs range from $15 for a copy of Dianetics to several hundred or several thousand dollars for a lecture series or course.