In AQUACLEW (Advancing the QUAlity of CLimate services for European Water), a project funded by JPI Climate and the ERA-NET Consortium 'European Research Area for Climate Services (ERA4CS), we examined different ways of improving the usability of existing Climate Services across Europe tackling key aspects in Climate Services improvement: user engagement, lack of resolution, uncertainties, and the need of an evaluation. The rationale of the project is based on an interactive process between service developers and users in seven study cases across Europe assessing the implications of Climate Service' advancement in users' decision-making process. A qualitative evaluation assessment allowed us to identify-four pillars when improving the quality of the climate services in the water sector: (1) Robustness, accounting for better quality of the service' information in certain aspects; (2) Recruitment, understood as a need of involving users more actively in CS structures; (3) Reform, highlighting the possible need for changes in both the service structure and users mindsets; and (4) Reflection, as a process of continuous evaluation of the climate service during its life.