There are three hierarchies - the Heaven of Form, the Heaven of Creation and the Heaven of Paradise; and each of these levels has three groups of Angel.

THE HEAVEN OF FORM
The Angels of this realm are Divine Messengers and those closest to us on Earth. They help us bring order and happiness into our lives. There are 3 groups of Angels in this realm:

The Archangels - Messengers from the Divine to mankind, they offer us spiritual sustenance and inspiration. They provide us with revelation and supply all the tools we need for our spiritual development. They are protectors of humankind and have specific functions which aid the collective and universal spirit of the human race. There are 5 prime Archangels to call on when you need help: Michael (for protection), Gabriel (for mercy), Metatron (for adundance), Raphael (for healing) and Uriel (for peace).
The Guardian Angels - are each assigned to a particular person and they watch over individuals' spiritual growth throughout their lives and protect and defend their souls. The Guardian Angels represent the different stages of development we pass through in our lives. They stand as a symbol of the passages we all make as we mature and develop along our path. There are 9 Guardian Angels to call on for help: Guardian Angel of Children, Guardian Angel of Youth, Guardian Angel of Young Love, Guardian Angel of Young Adults, Guardian Angel of Maturity, Guardian Angel of Health, Guardian Angel of Creativity, Guardian Angel of Spiritual Growth, Guardian Angel of Service.
The Angel Princes - are the protectors, helpers and guides of races, nations, cities and towns. They have a strong and powerful influence on the destiny of great masses of people. They represent the collective spirit of different types of humanity and their combined presence amounts to the spirit of a place. They denote the four compass points, the four elements and the four psychological functions which make up the conscious mind: thinking, feeling, sensation and intuition. In this way, the Angel Princes relate directly to every one of us and to our lives. They focus on the psychological aspects of the three-dimensional world and can assist us in understanding the essence of our situations. There are 4 Angel Princes: Angel Prince of the South, Angel Prince of the North, Angel Prince of the East, Angel Prince of the West.


THE HEAVEN OF CREATION
The Angels of this realm are Divine Governors and they help us to love and understand one another. There are 3 groups of Angels in this realm:

The Powers - Specifically offer us peace, harmony and serenity. Their heavenly function is to guard our souls, which thrive best in an atmosphere of tranquility and peace. They keep track of human history - birth and death and rebirth and are the keepers of the Akashic Records. There are 3 Angel Powers: The Angel of Peace, The Angel of Serenity, The Angel of Harmony.
The Virtues - Teach us the love of freedom and the sanctity of faith. Their heavenly function is to transform our thoughts into matter and they are the essential link in the process we call manifestation - that is, what we wish for and desire can be transformed into material reality by our firm intention to create it. There are 3 Angel Virtues: The Angel of Freedom, The Angel of Trust, The Angel of Faith.
The Dominions - Offer mankind the quality of mercy. They help is reconcile our past and find forgiveness in our hearts and bring us the gift of wisdom, enabling us to live in a state of grace. They also assist the Guardian Angels in looking after their mortals. There are 3 Angel Dominions: The Angel of Reconciliation, The Angel of Mercy, The Angel of Forgiveness.


THE HEAVEN OF PARADISE
The Angels of this realm are Divine Counsellors, offering us the greatest gifts of love and wisdom. There are 3 groups of Angels in this realm:

Seraphim - Associated with the very essence of creation, in their light they are the creators of miracles. They transmit God's energy to create the elemental substance of which life is formed and which is pervasive throughout the universe. There are 3 Seraphim: The Angel of the Miracle of Love, The Angel of the Essence of Love, The Angel of Eternal Love.
Cherubim - Guardians of the entrance to Paradise, they are the bearers of the ultimate wisdom within the universe. They aid all who are associated with wisdom and they offer strength to all who are attuned to the word of God. They are not the chubby children so often depicted in angelic art - rather they are the purity of spirit that is embodied in young children who know that they are safe and deeply loved. There are 3 Cherubim: The Angel of Wisdom, The Angel of Discernment, The Angel of Knowing.
Thrones - Are the closest angelic form to the Divine Source itself. They exist beyond form and yet their angelic function is to transform thoughts into matter. They exist at the level of pure thought and are the conductors of the vibration of God's love unto material form. They act as the eyes of God and take the form of swirling streams of coloured light. The realm of the Thrones is the highest level the Angels can ascend. There are 3 Thrones: The Angel of Being, The Angel of Power, The Angel of Glory.