The dissolution of Gibson's partnership coincided with the start of construction of the new Episcopal Cathedral of All Saints in Albany, having won a competition the previous year.

[2] A project of Bishop William Croswell Doane, the building was the first American Episcopal cathedral to be conceived on the scale of its European counterparts.

[3] In 1888, having completed the first phase of the cathedral and having been commissioned to design a bank for the United States Trust Company in New York, Gibson relocated to that city.

His entry into the 1889 competition to design the Cathedral of St. John the Divine in New York drew from a variety of sources, with an overall effect of the Decorated period of English Gothic architecture.

Several competitors, including Gibson, alleged that Gilbert had conspired with Supervising Architect of the Treasury James Knox Taylor, his former business partner, to be awarded the commission.

[9] He was a member of the AIA Board of Directors, and served two terms as president of the Architectural League of New York.

Lydia, his eldest daughter, was an artist who would become a noted Socialist activist and was married to Communist leader Robert Minor.

Hester, the youngest, was less public with her politics but was involved in the work of the International Labor Defense and made the news in 1939 when she bailed out jailed Communist leader Earl Browder.