Dillon helped form the Dubuque United Labor Participation Committee in 1978. In 1985 he attended the prestigious National Issues Forum in Boston. Often listed among the ten most influential people in Dubuque, Dillon held many leadership positions in Dubuque organizations. He served on the board of trustees of the United Way and HMO. Dillon also served on the Civil Service Commission, GREATER DUBUQUE DEVELOPMENT CORPORATION Board, executive board of the United Labor Participation Committee, Human Rights Commission, and the Tri-States Alcohol Drug Abuse Committee. Dillon was vice-president of Dubuque’s 1976 Bicentennial Committee.