In this chapter, several aspects of laparoscopic peritoneal lavage and its potential role in the treatment of perforated diverticulitis with purulent peritonitis are discussed. In the past decades, this non-resectional strategy has gained increased interest, due to a potential reduction in morbidity and mortality as compared to resectional strategies, such as Hartmann’s procedure or sigmoid resection with primary anastomosis. Moreover, the avoidance of a diverting stoma, with its subsequent risk of stoma-related and reversal-related complications, was also identified as a potential advantage. However, the role of lavage has also been questioned, mainly because of the risks that are inherent to leaving the diseased colonic segment in situ, such as the risk of ongoing sepsis or missing an underlying colorectal malignancy. For these reasons, the role of laparoscopic lavage is still a much-debated topic, and this chapter aims to present a comprehensive overview of the current available evidence on the treatment outcomes of laparoscopic lavage, including morbidity, mortality, patient-reported outcomes, and healthcare costs. Moreover, it aims to summarise the several conclusions drawn in the abundance of recently published meta-analyses on this topic, as well as the recommendations provided in national and international guidelines on the management of diverticular disease. In addition, the technical aspects of the procedure and the potential risk factors associated with the failure of lavage are discussed.