When the Discalced Carmelites were juridically erected in 1593, its superiors retained the power granted by Pope Nicholas V in the bull "Cum nulla fidelium conventio" of 7 October 1452 to incorporate lay persons as members of the Order.

[citation needed] In the late 17th century, efforts were made that led to the erection of a secular order, beginning in Belgium and then in France and Italy.

In 1848 a short book on the Third Order, the "Breve [C]ompendio", was published in Florence, Italy, being merely an abridged version of the Rule of Marseille.

These three sources of legislation, in that order, move from general to more particular rules which are approved by the Church for their particular vocation and circumstances.

As models of this ancient way of life, they study the writings and imitate the lives of the many saints of the Discalced Carmelite Order, especially St. Teresa of Jesus and St. John of the Cross, both doctors of the Church.

Doctrines include "gladly mortify themselves in union with the Sacrifice of Christ," and their "interior life must be permeated by an intense devotion to Our Lady."

[9] Depending on their existing provincial statutes and with the approval of their local council, their communities accept Catholics in good standing in the Church who meet the age requirement into formation.

[11] Catholics begin by discovering a community of Seculars which they visit for monthly meetings and may eventually join.

[14] The Order has many members in the Philippines, which it attributes to the great devotion to Our Lady of Mount Carmel in that nation.