Most patients with colorectal liver metastases are treated within a multimodal therapy regime whereby liver resection is a key point in the curative treatment concept. The achievement of an R0 situation is of vital importance for long-term survival. Besides general operability and the assessment of comorbidities, resection depends on the quality of liver parenchyma (functional resectability) and the anatomical position of the tumor (oncological resectability). The improvement of operation techniques and perioperative medicine nowadays allow complex surgical procedures for metastasis surgery. This article presents the methods for the assessment of resectability and modern strategies of preoperative conditioning as well as approaches for extended liver resection.