Case transfer authority permits commissioner and board to reassign gift-tax cases among officers with hearing and jurisdiction safeguards. The amendment permits the Commissioner and the Board to transfer any gift-tax case among subordinate Gift-tax Officers, subject to procedural safeguards: generally providing the assessee a reasonable opportunity to be heard and recording reasons for the transfer, with a locality exception when offices are in the same city. Transfers to multiple officers create concurrent jurisdiction, and those officers must discharge functions under written general or special orders of the Board or Commissioner and under directions the Inspecting Assistant Commissioner may issue.