Surgical resection has offered the best option for prolonged survival in patients with colorectal liver metastases. Limiting factor for major liver resections is the size of the future liver remnant (FLR). In case of normal liver function, 30% of the total liver volume is considered to be sufficient to maintain adequate liver function after resection. In an attempt to further increase "resectability" criteria for patients with too small FLR surgical and interventional maneuvers such as portal vein embolization and portal vein ligation in two-stage hepatectomies have been implemented, but they need an interval of 4-8 weeks to achieve sufficient hypertrophy. In order to obtain adequate but rapid parenchymal hypertrophy a new surgical two-step technique, ALPPS, was introduced for oncological patients requiring extended hepatic resection with limited functional reserve. Both procedures can be performed with acceptable morbidity and mortality.