Police officers accept the need to work unpopular hours as Long as these hours are shared fairly. Modern shift systems are usually based on the principle of equity, with the effect that the same number of officers are generally on patrol at any time, regardless of the needs of the service. A knowledge of alternatives may help to overcome this problem. Because British police establishments are usually staffed with men per 24-hour post, this figure serves as the basis for the following review of shift systems. Shift systems available to police are (1) the three shift system, in which manpower is evenly distributed over the 24 hour day; (2) four shifts, which also result in an even distribution of manpower over 24-hours, but include a reserve since only four of the five policemen are required to cover the period; (3) five shifts, which provide 100 tours of duty per 28-day period (accounting for time off) when only 84 are needed for basic cover; and (4) six or more shifts, which allow greater flexibility, but require additional personnel. Also discussed are half shifts overlapping or structured patrolling, and flexible shifts. Graphs illustrate typical department workloads and the practical effects of each shift system.