The Court of Sessions was one of the first courts established in California by the 1849 California Constitution. As organized by the California Legislature in 1850, the Court of Sessions in each county was presided over by the county judge. He was assisted by two associate justices elected from among the county's justices of the peace. After receiving an indictment or presentment from the county's Grand Jury, the Court heard criminal cases of assault, assault and battery, breach of the peace, riot, affray, petit larceny, and all misdemeanors punishable by a fine not exceeding $500 or imprisonment not exceeding three months or both such fine and imprisonment. The Court of Sessions was abolished in 1863 when the California Legislature reorganized the California courts. This publication comprises three sections. The first section is a table which gives for each Sonoma County Court of Sessions case its California State Archives case file number, the name(s) of the defendant(s), the charge, the date of the indictment or presentment, and the volume(s) and page number(s) in the existing Sonoma County Court of Sessions bound volumes (minute books, judgment book, and register) in which each case is recorded. The second section is a narrative arranged chronologically describing the proceedings of each Court of Sessions term. The third section provides a full-name index for the entire publication.