There are only two requirements for a man to join the Knights of Columbus: that he be a practical Catholic as understood by the Church, and that he be 18 years of age or older.
While dues-paying membership is only for Catholic men, most council programs are open to the member's entire family, including social and family activities, scholarships, volunteer service programs and insurance benefits.
Candidates join local units, called "councils," most of which are based in one Catholic parish, or in the community at large. The candidate takes part in initiation degrees that explain the Knights of Columbus' four principles: Charity, Unity, Fraternity and Patriotism. He is considered a "Knight" after taking his First Degree, but he is encouraged to advance through the Second and Third Degrees and on to the Fourth Degree, whose members promote the virtue of patriotism by serving in honor guards, color corps and promoting respect for country and the flag.