Mirra Alfassa (1878-1973) - otherwise known as "the Mother" (not to be confused with a number of female gurus who bear the same title), was an extraordinary spiritual Teacher. A Parisian of Egyptian descent. After having many spiritual and occult experiences of her own, she left for Algeria in 1906 to learn occultism more thoroughly, under the guidance of the little-known adept Max Theon and his wife Alma. She then returned to Paris, where she set up her own spiritual-esoteric circle. Later, with her second husband she traveled to India, where in 1914 she met Sri Aurobindo, who had recently taken refuge in Pondicherry. She later left for Japan and after some years returned to Europe. In 1920 she returned to Pondicherry, where she remained for the rest of her life. Together with Sri Aurobindo, the Mother, as she then became reverently known ("The Mother" in fact is simply an Indian title of respect for a female Spiritual Teacher, just as male Teachers are called "Baba", meaning "Father"), worked on a process of spiritual transformation totally different to that of previous yogas: rather than being simply a self-transformation in order to attain the state of individual eternal transcendence or Moksha, it was work on transforming and divinising the entire planetary consciousness.
Some of the Mother's important insights have been recorded in The Agenda
In perusing Mirra's writings one realises that she is a master at conveying the Truth in the simplest and at the same time the most profound way.
Bernard's site for Sri Aurobindo and the Mother - selected words and images of Sri Aurobindo and The Mother - (site no longer being updated)
The Mother page
The Mother - good autobiographical and biographical material
The Mother's Service Society
The Mother - Wikipedia page, which has been something of a battleground, considering the very materialistic worldview (at best pluralistic, but even there not much) of the majority Wikipedia commubnity. I regret contributing to this page, and will not again compromise in that manner. But were I to write what I understood it would be deleted, same with the Sri Aurobindo page. The Mother's life cannot be defined or described in terms acceptible to the modern Western consensus worldview, nor can that of any Realiser or Diviniser. So I leave it to others to work on this page. In any case (at the time of writing this - 23 Dec 09) it is not as good as the page on Sri Aurobindo