A major challenge in statistics is to make inferences in the presence of measurement error or mismeasurement variables. Such mismeasurements appear in various contexts such as econometrics, biology or medicine. The paper by Carroll, Chen and Hu is completely in line with this challenging task. In this context, I would like to express my sincere and great appreciation for their contribution to this topic. It is a great pleasure for me to have the opportunity to contribute a discussion of this paper.