Groundwater is a crucial resource for sustaining life and supporting economic development across the Middle East and North Africa (MENA) region, where water scarcity remains a significant and persistent challenge. However, growing pressures from rapid population growth, intensive agricultural practices, industrial activities, and unregulated wastewater disposal have led to widespread groundwater contamination. This chapter provides a comprehensive review of the sources of groundwater pollution, monitoring techniques, and remediation strategies relevant to the MENA context. It outlines the hydrogeological characteristics of major aquifers and synthesizes findings from existing research to identify key sources of contamination—including agricultural inputs (e.g., pesticides, nitrates, salinization), industrial discharges (e.g., heavy metals, organic pollutants), domestic and municipal wastewater, naturally occurring geogenic substances (e.g., fluoride, arsenic, salinity), and excessive groundwater abstraction, which contributes to seawater intrusion in coastal zones. The chapter emphasizes the cumulative impacts of these pressures on groundwater quality and regional water security. Furthermore, it explores various assessment and monitoring methods employed to detect and evaluate groundwater contamination across the region. It also reviews successful case studies, assesses the effectiveness of remediation approaches, and discusses the technical, institutional, and policy challenges impeding sustainable groundwater management. Finally, the chapter offers strategic recommendations to enhance groundwater protection, promote Integrated Water Resources Management, and foster regional collaboration in addressing transboundary aquifer issues. These insights aim to guide the development of effective, context-specific remediation strategies tailored to the unique environmental and hydrological conditions of arid and semi-arid regions, particularly within the MENA region.