The development of GRASS was started by the USA-CERL to meet the need of the United States military for software for land management and environmental planning. A key motive was the National Environmental Policy Act. The development platform was Unix running on VAX hardware. During 1982 through 1995, USA-CERL led the development of GRASS, with the involvement of many others, including universities and other federal agencies. USA-CERL officially ceased its involvement in GRASS after release 4.1 (1995), though development had been limited to minor patches since 1993. A group formed at Baylor University to take over the software, releasing GRASS 4.2. Around this time, a port of the software to Linux was made. In 1998, Markus Neteler, the current project leader, announced the release of GRASS 4.2.1, which offered major improvements including a new graphical user interface. In October 1999, the license of the originally public domain software GRASS software was changed to the GNU GPL in version 5.0.