The most far-reaching consequence of Jack Morgan's stewardship was his decision to establish the Morgan as a public institution. In February 1924 Morgan transferred its ownership to a board of trustees along with a $1.5 million endowment. The indenture of trust provided for the use of the collections for research, the establishment of a gallery of art, and other such activities as the trustees deemed appropriate and desirable. The institution became a public reference library by a special act of the legislature of the State of New York, and Belle Greene was named its first director. Since Greene's retirement in 1948, there have been four directors of the Library—Frederick B. Adams, Jr. (1948–69), Charles Ryskamp (1969–87), Charles E. Pierce, Jr. (1987–2007), and William M. Griswold (2008–present).
What principally attracted Pierpont Morgan were beautiful works of art that also had a place in history. As The Morgan Library & Museum continues to increase its holdings—through purchases, generous gifts, and bequests—it does so in the same spirit.