Liver resection is the treatment of choice for patients with colorectal liver metastases(CLM).However,major resections are often required to achieve R0 resection,which are associated with substantial rates of morbidity and mortality.Maximizing the amount of residual liver gained increasing significance in modern liver surgery due to the high incidence of chemotherapyassociated parenchymal injury.This fact,along with the progressive expansion of resectability criteria,has led to the development of a surgical philosophy known as “parenchymal-sparing liver surgery”(PSLS).This philosophy includes a variety of resection strategies,either performed alone or in combination with ablative therapies.A profound knowledge of liver anatomy and expert intraoperative ultrasound skills are required to perform PSLS appropriately and safely.There is a clear trend toward PSLS in hepatobiliary centers worldwide as current evidence indicates that tumor biology is the most important predictor of intrahepatic recurrence and survival,rather than the extent of a negative resection margin.Tumor removal avoiding the unnecessary sacrifice of functional parenchyma has been associated with less surgical stress,fewer postoperative complications,uncompromised cancer-related outcomes and higher feasibility of future resections.The increasing evidence supporting PSLS prompts its consideration as the gold-standard surgical approach for CLM. Liver resection is the treatment of choice for patients with colorectal liver metastases (CLM) .However, major resections are often required to achieve R0 resection, which are associated with substantial rates of morbidity and mortality. Maximalizing the amount of residual liver increased increasing significance in modern liver surgery due to the high incidence of chemotherapyassociated parenchymal injury.This fact, along with the progressive expansion of resectability criteria, has led to the development of a surgical philosophy known as “parenchymal-sparing liver surgery” (PSLS) .This philosophy includes a variety of resection strategies, either performed alone or in combination with ablative therapies. A profound knowledge of liver anatomy and expert intraoperative ultrasound skills are required to perform PSLS appropriately and safely. There is a clear trend towards PSLS in hepatobiliary centers worldwide as current evidence indicates that tumor biology is the most important predictor of intrahepa tic recurrence and survival, rather than the extent of a negative resection margin. tumor removal avoiding the unnecessary sacrifice of functional parenchyma has been associated with less surgical stress, fewer postoperative complications, uncompromised cancer-related outcomes and higher feasibility of future resections. increasing evidence supporting PSLS prompts its consideration as the gold-standard surgical approach for CLM.