The Enneagram Made Easy: Discover the 9 Types of People A great book for those new to the Enneagram - accessible, accurate and funny.
Principles of – The Enneagram: The only introduction you’ll ever need Another good introduction to the Enneagram - concise and practical.
The Enneagram: Understanding Yourself and Others in Your Life Although an old book this is still a useful resource for a deeper understanding of the Enneagram.
Enneagram in Love and Work: Understanding Your Intimate and Business Relationships An invaluable guide to relationships between types, in love and work, it describes how different types get along and points out potential problem areas.
The Essential Enneagram: The Definitive Personality Test and Self-Discovery Guide Concise and affordable - if you want to find out what type you are, buy this book.
Enneagram Transformations: Releases and Affirmations for Healing Your Personality Type For those familiar with the Enneagram, affirmations of what is good about your personality and releases for self-defeating behaviour.
The Literary Enneagram: Characters from the Inside Out Provides a deeper understanding of character by looking at literary examples of the different Enneagram types, wings and subtypes.
The Enneagram Movie and Video Guide: How to See Personality Styles in the Movies Does the same thing with films.
What's My Type?: Discovering Your Primary Compulsive Patterns and Breaking Free to Fulfil the Potential of Your Personality Type The only book I have which goes into other triad combinations such as least preferred centre. An invaluable resource.
The Enneagram for the Spirit: How to Make Peace with Your Personality and Understanding Others Written by a yoga teacher it teaches the Enneagram in combination with meridians and chakras, and gives a yoga exercise for each type.
Enneagram And Kabbalah 2Nd Edition: Reading Your Soul An alternate theory of how to map the Enneagram onto the tree of life.
Character and Neurosis: An Integrative View Written by the man who brought Ichazo's teachings to California and hence the world, draws parallels between the Enneagram, DSM-III and more.
The Fragrant Mind: Aromatherapy for Personality, Mind, Mood and Emotion Although the author does not mention the Enneagram by name she does describe nine different aromatherapy personality types which correspond with the Enneatypes.