This paper examines the effects of object loss on narcissistic equilibrium from a developmental perspective. Such effects vary, depending on when the loss occurs in relation to the process of self-object differentiation, as well as on other characteristics in the loss situation. An effort is made to clarify the particular narcissistic elements which may be identified as involved in the experience of psychic pain following a loss. To this end, a distinction is made between feelings of omnipotence, of self-constancy, and of self-esteem, and their different developmental bases illustrated with clinical examples.