Laparoscopic ultrasound (LUS) increases patient safety by allowing the surgeon to see beyond surfaces of organs. LUS, however, is not in widespread use due to long learning curve and difficulties in interpreting the ultrasound images. In this paper, we highlight LUS's many advantages and its indispensable nature in laparoscopic liver procedures. The focus is the use of LUS in diagnosis and treatment of hepatocellular carcinoma and colorectal metastasis. The majority of patients have associated liver cirrhosis, and are terminally ill. Therefore, it is important to avoid unnecessary surgical trauma. LUS is sensitive in the detection of small liver lesions that are often missed by other preoperative imaging methods. This makes LUS an excellent tool for diagnostic and therapeutic purposes. Our overview focuses on procedures relating to hepatocellular carcinoma and colorectal metastasis where LUS is used and has been proven to benefit patient survival and potentially improve quality of life.