Abstract: A connector position assurance system is provided for an electrical connector adapted for mating with another mateable connecting device. The connector includes a housing having a guideway and a stop surface near the guideway. A primary flexible locking arm on the housing includes a latch for mechanically interlocking with a cooperating latch of the mateable connecting device. A connector position assurance (CPA) device is slidable along the guideway between a first position allowing movement of the locking arm and mating of the connector with the mateable connecting device, and a second position blocking movement of the locking arm away from a latched position. The CPA device includes a flexible stop arm engageable with the stop surface on the housing to prevent the CPA device from moving from its first to its second position.