Isidore Williem Schlesinger (Bowery, New York City, 15 September 1871 – Johannesburg, 1 March 1949) was a business tycoon and pioneer of the South African Entertainment industry.

[1] At 1.58 metres tall, he was nicknamed "Little Man", and was a significant figure in the South African Business world with interests in numerous economic sectors.

Schlesinger spent his childhood on the outskirts of the Bowery, on the East Side of New York City, where as a boy, he helped the family make an income by forging hair clips and selling newspapers.

According to another source, he was still an American citizen during the war and enjoyed considerable freedom as such, until the disruption to commerce led him to return to America, from there moving on to Ireland to sell the same insurance.

Until 1904, the Trust developed new neighborhoods in Port Elizabeth (Mount Pleasant) and Johannesburg (Orange Grove, Houghton, and Killarney) where salary-earners were given the opportunity to mortgage homes, a first in South Africa.

In the 1920s, Schlesinger helped found South Africa's first radio stations when he took over the struggling national broadcasting service, which at the time had only 20,000 license holders.

He owned controlling interests in retailers, banks, advertising agencies, a hotel chain, Catering firms, theme parks, agriculture, canneries, diamond grinders, and newspapers, and was the chairman of more than 80 companies.

His effort to found a large trust, however, failed afterwards; so did his entry into the Johannesburg newspaper market with the Sunday Express and his news service, Africopa.

The competition from established outlets such as The Star and The Rand Daily Mail, and the South African Press Association (SAPA), respectively, was too strong, but his advertising agency was one of the largest in the region.

Dr. M. Arkin described Schlesinger in the Suid-Afrikaanse Biografiese Woordeboek as "a short, sturdily built man, ...always dressed impeccably, [who] devoured all kinds of reading material.

', as his colleagues and staff called him, was someone with great [physical] energy who worked long hours, especially when it came to businesses which served as a touchstone for his salesmanship and economic acumen.