As early as March of 1918, The Citizens Committee of Five Thousand became The Citizens' League of Kansas City and Jackson County. Meeting in the Tabernacle of the Men's Bible Class of the First Baptist Church at Linwood Boulevard and Olive Street, the group effected a permanent organization and adopted a constitution. They planned to take an active part in city elections as watchers.

In 1934, the Citizens' League was reorganized and renamed the Citizens Association of Kansas City, Missouri, by Rabbi Samuel Mayerberg. At that time, corruption was rampant at City Hall. Vote stealing, bribery, and "country bookkeeping" were the order of the day. In 1940's "clean sweep" crusade, the Citizens Association successfully ousted the Pendergast political machine that had a stranglehold on City Hall. This campaign, billed as the "Battle of the Brooms", included a band of 7,500 women who wore badges depicting brooms. The Citizens Association became the dominant force for reform and good government for the next 65 years.

In recent years, Kansas Citians have been embarrassed by public corruption involving various members of the City Council. The Citizens Association has rededicated itself year after year to providing careful and thorough screening of candidates for Mayor and City Council, recommending only those persons who have demonstrated a high level of integrity and commitment to open, honest and fair government.