Lillian B. Williams recently became the first nurse to be elected to the board of trustees of the National Association of Children's Hospitals and Related Institutions. A member of the Children's Hospital staff since 1964, Williams also serves on the executive committee of the American Nurses Association Council on Nursing Administration. She is also a member of the D.C. Nurses Association, the American Society of Hospitals and the American Association for Child Care in Hospitals.

Arthur D. Lewis was recently named chairman of the board of the American Bus Association. He will be succeeded as president and chief executive officer by Norman R. Sherlock. The association's board of directors also chose Dr. Francis Mulvey, of Boston, to succeed Frederick H. Mueller as vice president of research. Mueller will retire at the beginning of 1982.

Paul M. Barth was recently appointed legislative coordinator for the National Small Business Association. He was formerly a business counselor for General Business Services Inc., a consulting firm for small businesses.

Patricia Dianne Jacobs has been named a Certified Association Executive by the American Society of Association Executives. Jacobs, who is president and chief administration officer of the American Association of Minority Enterprise Small Business Investment Companies Inc., received certification after passing an exam which tests association management skills. Five years of experience as a staff executive or three years experience as chief executive of an association are also required for designation as a Certified Association Executive.

Harry Martens Jr., president of Martens Volvo of Washington Inc. and Martens Marlow Datsun, has been chosen as the Washington, D.C., representative of the National Automobile Dealers Association board of directors. Martens is also vice president of Martens Chevrolet in Silver Spring and a director of Suburban Bancorporation and the Suburban Trust Co.

Linda S. Jenckes will return to the Health Insurance Association of America as vice president for federal affairs after a one-year stint at the Department of Health and Human Services. Jenckes is currently principal deputy assistant secretary for legislation at HHS. She entered the public sector early this year as deputy assistant secretary for health.

Jed Casey, vice president of M.S. Ginn and Co., has been elected 1981-82 vice chairman of the Retailers Division of the National Office Products Association.