The GMT system was initiated in late 1987 at Lamont-Doherty
Earth Observatory, Columbia University by graduate students Paul
Wessel and Walter H. F. Smith. Version 1 was officially introduced
to Lamont scientists in July 1988. GMT 1 migrated by word of mouth
(and tape) to other institutions in the United States, UK, Japan,
France and attracted a small following. Paul took a Post-doctoral
position at SOEST in December 1989 and continued the GMT development.
Version 2.0 was released with an article in EOS, October 1991, and
quickly spread worldwide. We obtained minor NSF-funding for GMT version 3.0 in 1993 which was released with another article in EOS
on August 15, 1995. Significantly improved versions (3.1, 3.2, 3.3,
3.3.1-6) were released between Novenber 1998 and October 2000, culminating in the
April 2001 release of 3.4. GMT now is
used by 
6,000 users worldwide in a broad range of disciplines.