What is khilafah, and how is a successor appointed in a Sufi order?

It is common for the shaykh of a Sufi order to nominate a successor, or several successors, from among the disciples to carry on the work of the order. This is succession, khilafah (also written khilafat).

The basis for this can be authenticated by the hadith narrated by Jubayr may Allah be pleased with him, who saw that a woman went to the Last Prophet ﷺ and spoke to him about something. When finished, the Beloved Prophet ﷺ told her to come and talk to him again, to which the woman asked, 'And if I do not find you?' as if to refer to his passing away. The Prophet ﷺ replied, "If you do not find me, then go to Abu Bakr may Allah be pleased with him." [Sahih al-Bukhari 3659]

Many so-called Sufis appoint successors for the purpose of perpetuating their order, regardless of whether the appointed is worthy of the position. As it is important to nominate a successor, it is equally important that the person be qualified for the role.

It is quite common that a son or a brother or a close relative is chosen. If it is because of the relation rather than the qualifications, then it jeopardises the sanctity of the order.