Technostress is a new concept in IS research which is still in the nascent stages of theoretical development. Despite a growing number of studies that examine the concept, a direct measure of technostress has yet to be developed, or distinguished from related affective states such as computer anxiety. In this paper, a unidimensional measure of technostress is created and validated in two different samples. In addition, based on the Affective Response Model, the technology induced state anxiety (TISA) concept is introduced and conceptually distinguished from computer anxiety and technostress. The discriminant validity of TISA, technostress and computer anxiety is tested in a nomological net of antecedents and objective technology performance outcomes using an experimental design. Partial Least Squares (PLS) modeling is used to test several hypotheses, the majority of which are supported. This work forms an important step in further understanding negative affective concepts related to technology use, and devising intervention mechanisms.