Water quality and quantity are under arising pressure from agricultural activities that may cause overexploitation of natural waters and pollutants runoffs (e.g., nutrients, pesticides). These stresses are also compounded by climate change effects. To address the complex challenges of agri-water management, the UNIVERSWATER consortium will adopt a ‘system of systems’ approach by developing and improving technologies designed to optimise water resources uses in a fully integrated way. A dedicated interdisciplinary and intersectoral consortium of 15 partners from six European countries will: a) develop innovative portable and in-situ sensors for a number of parameters and pollutants (salinity, nutrients, CEC, microbiological indicators) and b) couple them with earth observation imaging and advanced explainable and robust artificial intelligence techniques, as well as c) develop cost-effective, sustainable methods based on nature-based and technology-based solutions for water remediation at the point of need and d) promote the adoption of the developed methods through pricing incentive provision. These technologies will be integrated into decision support systems (DSSs) that will be tested at three case studies tackling on-farm treatment of dairy soiled water, mitigation of soil salination through water reuse, and optimisation of fertiliser/pesticide application for freshwater preservation. Going beyond, UNIVERSWATER will upscale these local DSSs into a common platform where a suite of DSS tools can be adapted to different situations after being tailored to the local factors, thereby developing a modular, extensible and holistic universal DSS.