This critical review by Jérôme Canivet, Alexandra Fateeva, Youmin Guo, Benoit Coasne, and David Farrusseng provides a comprehensive overview of water adsorption in Metal-Organic Frameworks (MOFs). The authors discuss the stability of MOFs in humid atmospheres and aqueous media, focusing on both reversible and irreversible mechanisms of water adsorption. They explore the impact of pore size, morphology, and flexibility on water adsorption properties, and present a detailed analysis of over 60 MOF samples. The review also covers the applications of MOFs in heat pumps, adsorbent-based chillers, and proton conductors, highlighting the relationship between structure and water adsorption. Additionally, the authors discuss the challenges and future directions in designing MOFs with controlled water sensitivity for various industrial and medical applications.This critical review by Jérôme Canivet, Alexandra Fateeva, Youmin Guo, Benoit Coasne, and David Farrusseng provides a comprehensive overview of water adsorption in Metal-Organic Frameworks (MOFs). The authors discuss the stability of MOFs in humid atmospheres and aqueous media, focusing on both reversible and irreversible mechanisms of water adsorption. They explore the impact of pore size, morphology, and flexibility on water adsorption properties, and present a detailed analysis of over 60 MOF samples. The review also covers the applications of MOFs in heat pumps, adsorbent-based chillers, and proton conductors, highlighting the relationship between structure and water adsorption. Additionally, the authors discuss the challenges and future directions in designing MOFs with controlled water sensitivity for various industrial and medical applications.