As gas turbine engines are scaled down in size, weight and cost, the EMS must also be reduced. Electronic automated EMS offers advantages over manual methods for power assurance, trend and limit exceedance monitoring, LCF and creep life recording.System cost is the main constraint on EMS for small gas turbines. The cost is proportional to the number of parameters measured which in turn determines the system capability. The constraints will preclude a full diagnostic capability. EMS costs may be reduced by “piggy-backing” with other systems.The paper concludes EMS is justified on small gas turbine engines. ARP 1587 is necessary for standardisation. Where EMS is to be integrated with other systems, detailed specifications are required.