The purpose of the Club Service is to foster the successful administration of a Rotary Club. Club Service is regarded by many Rotary Leaders as the most important part of the club mechanism because without a well-functioning club, little else can be performed via the other three Avenues of Service.
Club service involves regularly attending meetings, sponsoring new members, participating in club fellowship, taking part in programs, serving on committees and on the clubs' board of directors, and representing the club in outside activities. Rotarians have no obligation to strengthen their club, so all members should be encouraged to get involved in Club Service.

Duties

The chairman of the club service committee shall be responsible for all club service activities and shall supervise and coordinate the work of all committees appointed on particular phases of club service. The following sub-committees fall under the Club Service:

Attendance committee
Club bulletin committee
Fellowship committee
Magazine committee
Membership committee
Membership development committee
Program committee
Public relations committee
It is recommended that all club committee chairpersons maintain a close contact with the club Treasurer and Sergeant-at-Arms.

It is also recommended that the club service chairperson work with the club president on the program of at least two club assemblies. The first club assembly is held soon after the start of the Rotary year.

Source - Club President's Manual - 222EN, Manual of Procedure 2001