Gable CAD, or Gable 4D Series, was a British architectural computer-aided design package developed by Sheffield University in the mid-1980s under the leadership of Professor Bryan Lawson. It was spun out into Gable CAD Systems Limited and retained links with the university until its demise in 1996 when a court order was made for compulsory winding up. The assets of the company were acquired by Auxer in 1997 and aimed to complete the conversion of Gable CAD to Windows NT but this does not appear to have ever been released.