Sri Nisargadatta Maharaj (birth name: Maruti Shivrampant Kambli) (April 17, 1897 – September 8, 1981) was an Indian spiritual teacher and philosopher of Advaita (Nondualism), and a Guru, belonging to the Inchgiri branch of the Navnath Sampradaya. Sri Nisargadatta was born on April 17, 1897, at break of dawn, the full moon in the month of Chaitra, to a devout Hindu couple Shivrampant Kambli and Parvatibai, in Bombay. The day was also the birthday of Lord Hanuman; hence the boy was named 'Maruti', after Lord Hanuman himself. In 1915, after his father died, he moved to Bombay to support his family back home, following his elder brother. Initially he worked as a junior clerk at an office but quickly he opened a small goods store, mainly selling bidis – leaf-rolled cigarettes, and soon owned a string of eight retail shops.

In 1924 he married Sumatibai and they had three daughters and a son.
In 1933, he was introduced to his guru, Sri Siddharameshwar Maharaj, the head of the Inchegiri branch of the Navnath Sampradaya, by his friend Yashwantrao Baagkar.

Following his guru's instructions to concentrate on the feeling "I Am", he utilized all his spare time looking at himself in silence, and remained in that state for the coming years, practising meditation and singing devotional bhajans.

After an association that lasted hardly two and a half years, Sri Siddharameshwar Maharaj died on November 9, 1936, though by that time he had done his task. Maruti had reached self-awareness. Soon he adopted a new name, 'Nisargadatta' meaning the one who dwells in the natural state. He was also appointed as the spiritual head of the Inchegeri branch of Navnath Sampradaya, the 'Nine Masters’ tradition, a place he retained through his life.

In 1937, he left Mumbai and travelled across India. Through realizing the shortcomings of a totally unworldly life and the greater spiritual fruitfulness of dispassionate action, he eventually returned to his family in Mumbai in 1938. It was there that he spent the rest of his life.

One of the 20th century's exponents of the school of Advaita Vedanta philosophy (nondualism), Sri Nisargadatta, with his direct and minimalistic explanation of non-dualism, is considered the most famous teacher of Advaita since Ramana Maharshi.

In 1973, the publication of his most famous and widely translated book, I Am That, an English translation of his talks in Marathi by Maurice Frydman, brought him worldwide recognition and followers.