Due to the widespread clinical use of imaging modalities such as ultrasonography, computed tomography and magnetic resonance imaging (MRI), previously unsuspected liver masses are increasingly being found in asymptomatic patients. This review discusses the various characteristics of the most common solid liver lesions and recommends a practical approach for diagnostic workup. Likely diagnoses include hepatocellular carcinoma (the most likely; a solid liver lesion in a cirrhotic liver) and hemangioma (generally presenting as a mass in a non-cirrhotic liver). Focal nodular hyperplasia and hepatic adenoma should be ruled out in young women. In 70% of cases, MRI with gadolinium differentiates between these lesions. Fine needle core biopsy or aspiration, or both, might be required in doubtful cases. If uncertainty persists as to the nature of the lesion, surgical resection is recommended. If the patient is known to have a primary malignancy and the lesion was found at tumor staging or follow up, histology is required only when the nature of the liver lesion is doubtful.