Taher Saifuddin (4 August 1888[a] – 12 November 1965[4]), also known as Tahir Sayf al-Din,[5] was the 51st and longest serving Da'i al-Mutlaq of the Dawoodi Bohras.

[6] Saifuddin adapted the modernisation in Western and European ideas, and established its benefits for the Bohras, whilst still steeped in the traditions and the culture of the community's Fatimid heritage.

[9][10] Taher Saifuddin was born to Mohammed Burhanuddin I and Amatullah Aaisaheba[11] on 4 August 1888[a] in Surat, British India (present day the state of Gujarat).

[30] His Holiness [Taher Saifuddin] is not only the heir to Fatimid tradition of learning, but has in the course of his fifty years of office wrestled with the problems of the modern age.

Literature and poetry, learning and teaching, organisation and administration, national and international harmony, commerce, industry and technology, these are the broad facets which received his diligent attention and filled every moment of his life.

[36] Saifuddin brought about a structural and functional change at Aljamea: He personally oversaw the standardization of the syllabus of each class and wrote numerous memoranda and treatises which were instilled into the curriculum.

[44][45] In a similar vein, Saifuddin established an organisation of Dawoodi Bohra men, Shabab ul-Eid iz-Zahabi, during the Golden Jubilee celebrations of his 50 years in the office of Dai al-Mutlaq,[46][47] exclusively for community service.

[57] To subsidize costs and facilitate marriages among the close knit Dawoodi Bohra, Saifuddin initiated Rasm-e Saifee (lit.

He along with the Nizam of Hyderabad were among the few Indian Muslims to contribute towards the renovation of Al Aqsa Mosque in Jerusalem:[63] Saifuddin also gifted the internal curtains which were kept in the Kaaba for decades to King Abdul Aziz of Saudi Arabia in 1354AH, with whom he kept warm relations.

The case was filed in 1917, during the British rule of India, by Sir Thomas Strangman, the Advocate General of Bombay, at the behest of Adamjee Peerbhoy's family against the 51st Dai al-Mutlaq of the Dawoodi Bohra, Taher Saifuddin.

[92] He is buried at Raudat Tahera, a mausoleum opposite Ghurrat-ul Masajid in South Bombay, constructed by his successor, Mohammed Burhanuddin.

[93] Saifuddin donated his home Saifee Villa in Dandi, Navsari where Gandhi stayed for ten days during his historic march from Sabarmati Ashram against the English Salt Laws, to Nehru in 1961.

[100] In 2009 Mohammed Burhanuddin founded Saifee Burhani Upliftment Trust (SBUT), a large-scale cluster redevelopment project in Bhendi Bazaar and dedicated it to his father, Saifuddin.

[101] The Government of Maharashtra plans to develop Kamathipura, one of the oldest neighborhoods of South Mumbai, after the cluster redevelopment model pioneered by SBUT.