Marshall Estus Sehorn (June 25, 1934 – December 5, 2006) was an influential American A&R man, songwriter, music publisher, and entrepreneur. Born in Concord, North Carolina, Sehorn played guitar in local bands while attending North Carolina State University. After graduating, he moved to New York City in 1958, joining the A&R staff at Bobby Robinson's Fury and Fire record labels. He played a crucial role in promoting Southern music and discovered singer Wilbert Harrison, whose hit "Kansas City" topped the US charts in 1959. Sehorn also signed Bobby Marchan and Lee Dorsey, the latter of whom he paired with songwriter Allen Toussaint.

After the collapse of the Fire and Fury labels in 1963, Sehorn stayed in New Orleans, establishing Rhinelander Music and co-founding the Sansu record label with Toussaint. They signed artists like Betty Harris and worked with The Meters, becoming key figures in New Orleans' music scene. They also built the Sea-Saint Recording Studio, attracting artists such as Dr. John, The Neville Brothers, and Paul McCartney.

In the 1970s, Sehorn shifted to music licensing, founding companies like Blue Dog Express. However, legal issues arose when he attempted to acquire rights to the Chess Records catalogue, resulting in a lawsuit from MCA Records. Sehorn lost the case, leading to bankruptcy, and his companies' assets were used to compensate artists like Betty Harris who had been denied royalties. Despite these challenges, Sehorn's impact on R&B and New Orleans music remains significant.