The true value of groundwater is hidden beneath the ground. Often, the general public and policy-makers are not fully aware of the importance of this precious resource, even though groundwater provides nearly 50% of all drinking water. While the pressure on groundwater has been steadily increasing, this invisible resource continues to receive less attention than it deserves. This Global Water Security Issues (GWSI) Series 3, The Role of Sound Groundwater Resources Management and Governance to Achieve Water Security explores various case studies of tools and analyses of management, groundwater quality issues, transboundary aquifer management, and stakeholder engagement. The GWSI shines a spotlight on groundwater resources to highlight the importance of integrated water resource management and strengthened capacity for robust management decisions.