THE PEACE CORPS celebrated its 22nd anniversary last week, and maturity has not diminished the vitality and enthusiasm that has characterized this volunteer agency throughout its history. In New Frontier days, recent college graduates, usually generalists, flocked to the corps eager to bring American skills, culture and friendship to the Third World. The volunteers are still coming, and over 5,000 of them are serving in 62 countries today. Emphasis is placed on providing host countries with volunteers trained in agriculture, renewable energy resources and small-business skills as well as traditional education programs. And efforts have been made to place older volunteers. More than 300 over the age of 50 are now serving, including many married couples.

All who volunteer, survive the selective screening process and rigorous training and serve under hardship conditions are special. But some are standouts. A Detroit couple--he is 87 and she is 84--have just signed up for their second two-year hitch. A blind volunteer, recently returned from Ecuador and now working in Peace Corps headquarters here in Washington, not only completed his tour with distinction; he also organized and ran a Special Olympics for the mentally retarded, the first such event held in Latin America.

Eight deaf volunteers--trained here at Gallaudet College--set up a program for teaching deaf children in the Philippines. One volunteer, a graduate of Gallaudet who is both deaf and a victim of cerebral palsy, spent her tour on the island of St. Vincent teaching two dozen deaf 6- to 8-year-olds. Before she arrived, these children had no knowledge of sign language and no hope for education. Now they can communicate, read and write and use basic math skills. Twenty-four children have been given hope, and their country has been given a model for teaching the handicapped.

More than 100,000 Americans have served in the Peace Corps. In large numbers they have entered government, particularly the Foreign Service and the U.S. Agency for International Development. Two returned volunteers now serve in the Senate, three in the House. Another, Mrs. Lillian Carter of Plains, Ga., had special influence with a president of the United States. All deserve praise but none more than those special volunteers who overcame their own physical handicaps to help others far from home. That spirit is America's finest export.