The authors should be commended for presenting such an innovative, elaborate elasto-plastic framework for predicting constitutive unsaturated soil response under isotropic stress states. One of the key aspects of the work is the authors' deep knowledge of the physical interactions that lie behind the mechanical behaviour of unsaturated soils. The proposed constitutive model and their associated conceptual framework provide an important improved understanding of soil behaviour. The present review is intended to offer some comments that further highlight the relevance of the work and its potential for further refinement and tuning.The objective of this review is twofold: