‎In this paper‎, ‎the concept of joint reliability importance (JRI) of two or groups of components in a coherent system with independent components have been studied‎. ‎The JRI is defined as the rate at which the system reliability improves as the reliabilities‎ ‎of the two or groups of components improve‎.

‎Generally‎, ‎the sign and the value of the JRI represent the type and the‎ ‎degree of interactions between components with respect to systems reliability‎.