The exercise of professional hydrogeology is a privilege that requires sound scientific and technical knowledge, field training and interpersonal skills. A skilled hydrogeologist is required to have ethics, deontology, integrity, eco-responsibility, leadership, and behaviour but also the acceptance of the high-standards and codes of ethics and boundaries to avoid discrimination and harassment. In addition, the hydrogeology practice must encompass the geoethical approach. Water supply and infrastructure design and construction for groundwater monitoring are not popular nowadays around the scientific and technical community. However, thousands and thousands of wells and boreholes are drilled worldwide annually, without appropriate hydrogeological support. A professional hydrogeologist cannot support, for example, policies of abandon of fieldwork, leaving the aquifer exploitation restrained to high levels of management and governance. Those practices must be developed through proper conceptual site modelling based on field and laboratory data, complemented by GIS mapping, geovisualization techniques, numerical tools to predict scenarios and climate change understanding. On the ethical point of view, this systematic methodology underpins personal scientific integrity but also a comprehensive understanding of the problem to solve. That includes the moral decisions to be made regarding the undertake of the pure and applied hydrogeology in the practice, as well as the professional appropriate use of the scientific advancements in groundwater science, technology, and management.