In marketing research, the definitions of constructs often involve a temporal dimension, which make them either an ephemeral state or a lasting trait or a combination of the two. However, researchers do not always confirm the temporal hypothesis used. There are various ways of going about such verification, but their implementation is sometimes tricky. The purpose of this paper is to clarify these techniques and their use. A model decomposing the variance of a constuct into stable, scalable and situational temporal components is put foward. This model is then used in two different case studies, one to test the temporal validity of a marketing construct viewed as a trait, the other to test the temporal validity of a marketing construct viewed as a state.