A Mufti is normally someone well-grounded in Islamic law, who got the ability from qualified teachers to issue formal legal rulings on matters in Islamic law. Reaching this status requires that one study the principle books of fiqh, principles of jurisprudence, books of fatawa (legal verdicts) and other related subjects, and then sit with Muftis and practice researching issues of fiqh and providing answers to them with reference to source books. Studies in other sciences are also important: e.g. aqida, tafsir and hadith. Muftis at times consult as a body on new issues that require much research.
In the Dars-e-Nizami system of the Indian Subcontinent (also followed in SA, UK and other countries), the Mufti course is done after completing the Alim course (6-8 years). The Mufti course takes 1-4 years. The institution gives the student permission to issue fatwas if he gained sufficient expertise. It is then up to him to further his research and keep abreast of fiqh texts and fatawa.
Some scholars who studied Islamic law well are also able to answer many questions, even though they haven’t completed the Mufti course. Over time they develop a proficiency and come to be accepted as scholars who can issue rulings. This was the case in the past and is still the case in many countries today.
Some countries only grant the title of Mufti to a scholar placed in the official position of Mufti in the city (e.g. Mufti of Damascus) or country (e.g. Mufti of Egypt), even though other scholars there have similar or greater ability to issue rulings but will not be given the title of Mufti.