The work of eight artists with autism from around the world will be emblazoned on a series of postage stamps launching in April in honor of World Autism Awareness Day.

The stamps will be issued by the United Nations Postal Administration starting April 2 and will be available at U.N. offices in New York, Geneva and Vienna. The postage is valid for mailing correspondence from any U.N. location globally.

Each year the U.N. Postal Administration issues stamps to call attention to seven different causes that are important to member nations. This is the first time that the U.N. will offer stamps to highlight autism awareness. In addition, the agency plans to release stamps this year focusing on endangered species, the environment and other issues.

Artwork for the stamps was solicited from artists with autism around the globe. The eight winners include five from the United States.

“It was an extremely difficult and challenging process to choose only eight designs from all of the artwork submitted,” said Rorie Katz, creative director for the U.N. Postal Administration. “All of us were personally touched by the stories of the artists and their families who are extremely passionate and supportive about raising awareness for autism.”

Winning designs feature everything from flowers to geometrics. Different stamps will be issued in New York, Geneva and Vienna, with two designs included on each sheet of 20 stamps, according to the U.N. Postal Administration.

Officials say they expect to make about 1 million of the autism stamps available to the public.