In the U.S., John Held, Jr. has been indefatigable in such efforts. Ruggero Maggi of Milan, Italy has also been particularly active. Closest to most Mail Artists' hearts was the 1988 International Shadows Project Show held in Hiroshima, organized by Shozo Shimamoto, Maggi, Held, and others. This show was international not only in its content but also in its organization and in the number of participants from all over the world who came together for this event. This show included work from previous shows organized by Maggi, including the Hiroshima Show.
Some pieces go back to the beginning of the decade.
It would be interesting to chart the course of these older pieces which have circled the globe several times in their course from show to show. Work from a 1989 show in Calexico, on the U.S.-Mexican border, sponsored by Harry Polkinhorn, and a 1990 show under my curatorship were also included. The global postal system established after World War II was a crucial factor in the growth of Mail Art from a limited genre practiced by Schwitters, Duchamp, and others into a decentralized, global, grass roots movement, owing a great deal to the efforts of Ray Johnson. It is interesting that while Mail Art has been expanding, two other movements have followed along similar lines. One of these is crane projects.