John Francis (Jack) Hennessy (1853–1924) went into partnership in an architectural practice in 1912 with his son, also named John Francis (Jack) Hennessy (1887-1955). The firm became known as Hennessy & Hennessy. In 1924, the older Jack retired and the younger Jack took over as the head of the firm, which continued under the same name, though it was sometimes referred to as Hennessy, Hennessy & Co. From 1925 to 1926, the firm expanded to include more partners and was briefly known as Hennessy & Hennessy, Keesing and Co and J.P. Donoghue. After 1926, the firm reverted to its original name, Hennessy & Hennessy, or Hennessy, Hennessy & Co. One of the major projects of the firm was the Great Court at the University of Queensland and the Holy Name Cathedral in Brisbane, the latter of which was never fully completed. Jack F. Hennessy died in 1955 and the firm continued to operate under the leadership of Leo Drinan. After Leo Drinan's death in 1967 the Brisbane branch was taken over by Martin Conrad and the Sydney office closed shortly thereafter. It continued to operate until 1967