Abstract: An infant seat/carrier alarm system designed to produce an audible or visual warning when the seat/carrier component is initially aligned on the base component, not locked onto the base component, or when the harness is in an unused state. The alarm system has a main circuit which includes a power source, an audible or visual alarm, a main switch, and two double pole switches all connected together in a series. The double pole switches are used to close the main circuit or connect it with a branching circuit thereto. The main circuit is designed to detecting the presence of the seat/carrier component aligned on the base component. Two double pole switches are disposed between the seat/carrier component and the base component which are moved between the two contact positions by the carrying handle when rotated between unlocked and locked positions. The branching circuit includes a normally closed, single pole switch located in the buckle of the harness.