A tool pusher (sometimes toolpusher) is an occupation within the oil drilling industry.
On a land drilling rig the tool pusher may be rig manager and responsible for all operations, but on drillships and offshore oil rigs, toolpushers are department heads in charge of the drilling department and reporting to the Master or Offshore Installation Manager (OIM) depending on the company - who in turn report to a shore-based rig manager. Other department heads include the Chief Mate and Chief Engineer.
Tool pushers are in charge of keeping the rig in all necessary tools, equipment, and supplies. They work closely in conjunction with the representative of the operating/exploration company (i.e., company man) in regard to the actual drilling of the well. In recent times, toolpushers also have taken on somewhat of an administrative role, as they frequently do paperwork related to the rig crew regarding payroll, benefits, and related matters. Toolpushers are also responsible for coordinating services with third party companies related to the drilling of the well.
Tool pushers usually start at an entry level position (i.e., a roustabout or roughneck) and work their way up over many years.