The Enneagram measures human personality by 9 basic types. However, instead of measuring surface traits, it gets below these and into motivations. Motivations can often result in the same behaviours, which is why people of the same motivation may appear just like each other on the outside -- or not. The Enneagram is mainly a diagnostic tool of one's emotional outlook on life. It will not cure one's problems, but may help point out their underlying fixations. It is also useful as a guide to how other people see the world differently.
The Nine Basic Types
Type One - Reformer
Perfectionistic, orderly, hard-working, ethical, conscientious. They can be very rational and idealistic, but can also be judgemental and convinced they are always right. Motivation: To be right, ethical, perfect.
Type Two - Giver / Helper
Generous, friendly, prideful, seductive, reassuring. They can be very loving and dedicated, but also possessive and manipulative. Motivation: To be loved, thanked, important in others' lives.
Type Three - Achiever
Ambitious, goal-oriented, adaptable, deceiving, presentable. They can be exemplars of "all you can be", but also shallow and arrogant. Motivation: To be admired by others, successful, a winner.
Type Four - Individualist
Creative, depressive, romantic, shy, unique. They can be profound artists who express the inexpressable, but also self-hating and clinging. Motivation: To understand the self, be unique, express themselves.
Type Five - Investigator
Insightful, theoretical, detached, eccentric, intense. They can be extremely brilliant and inventive, but also nihilistic and alienated. Motivation: To understand the world, find safety from it, become skilled.
Type Six - Loyalist
Loyal, skeptical, complex, paranoid, dependable. They can be excellent team players but get lost in scapegoating and fear. Motivation: To find security, resolve their paranoia.
Type Seven - Enthusiast
Enthusiastic, worldy, optimistic, scattered, accomplished. They can truly love life like no one else, but can fall victim to hedonism and excess. Motivation: To experience life, be happy, not miss out.
Type Eight - Chief / Challenger
Powerful, leading, aggressive, cruel, protective. They can be magnamious leaders who get the job done, but can become violent and terrorizing. Motivation: To be in control, strong, independent.
Type Nine - Peacemaker
Peaceful, receptive, complacent, forgetting, gentle. They can be relaxed and terrific friends, but can become unaware of reality and problems. Motivation: To be at peace, be in harmony with the universe.
The 9 types can mix like colors on a palette. However, mixtures with numerically adjacent types are particularly frequent and striking, and are called "wings". Hence, a 5's wing will either be type 4, or type 6 (or occasionally both). A 9's wing will either be type 8 or 1. It is also possible for someone not to have a strong wing, or to have elements of both wings.
Advocates of the Enneagram system suggest that, whilst it is a more difficult (and complex) system than the Myers-Briggs, but ultimately more meaningful, descriptive, and enlightening.
Don Riso and Russ Hudson of The Enneagram Institute have produced several Enneagram-based personality tests for personal, group, and business use. Basic, free tests are available at www.enneagraminstitute.com. Further, detailed information is also available at www.9types.com.