The United States issued this mint stamp on May 17, 1968, to publicize the work of law enforcement officers as protectors and friends of the people. The design features a policeman and young friend.

This mint stamp was issued on Oct. 26, 1964, in conjunction with the annual meeting of the National Extension Homemakers Council to commemorate the 50th anniversary of the Smith-Lever Act. The objective of the Smith-Lever Act was to improve home life in America. The design depicts a needlepoint sampler of an American farm scene.

This mint stamp, issued by the United States on September 11, 1964, commemorates the 50th anniversary of the founding of the world-renown mayo Clinic in Rochester, MN. The stamp also pays tribute to William J. Mayo and his brother Charles H. Mayo (doctors and surgeons).

This October 26, 1963 issue commemorated the 100th anniversary of city mail delivery. Before 1863, letter recipients would generally pick up their mail at the post office (you may have seen old letters with an address listing only a name, town, and state- no address was needed). The stamp design features artwork from Norman Rockwell: a postman flanked by a boy and dog.

The United States honored the 100th anniversary of the nursing profession with this December 28, 1961 issue. The training of nurses began in the United States with the outbreak of the Civil War. These training programs laid the foundation for the nursing profession. This mint commemorative stamp features a nurse lighting a candle.

This mint stamp, featuring an oil derrick, was issued by the United States on August 27, 1959 to commemorate the 100th anniversary of the completion of the first oil well at Titusville, Pennsylvania (constructed by Edwin L. Drake).

Depicting an allegory of the "Good Earth with Horn of Plenty," this mint stamp was issued by the United States on March 15, 1958. This issue commemorated the 100th anniversary of the birth of Liberty Hyde Bailey. Bailey was a famous botanist, author and teacher- his horticultural advances contributed to American prosperity.

Teachers of America and the National Education Association are honored on this mint stamp, issued by the United States on July 1, 1957. The design features a teacher, students, and globe.

The United States issued this beautifully engraved mint stamp (one of our favorite U.S. stamps) on June 9, 1947, to honor American Physicians. The design is from a painting by Sir Luke Fildes, titled "The Doctor."

This mint stamp sheet (single $5 stamp) from the Commonwealth of Dominca features Betty Boop as a Nurse holding a large spoon full of medicine. Issued on Oct. 1, 2001. The sheet selvage is inscribed with the appropriate Betty Boop copyright and trademark information.