PURPOSE: To compare the clinical usefulness of the half-Fourier rapid acquisition with relaxation enhancement (RARE) technique at T2-weighted magnetic resonance (MR) imaging of focal liver lesions with that of multishot RARE MR imaging and contrast material-enhanced helical computed tomography (CT). MATERIALS AND METHODS: Half-Fourier RARE and multishot RARE imaging and helical CT were performed in 48 patients with 102 focal liver lesions and in three patients with diffuse metastatic liver disease. Images were compared qualitatively and quantitatively for image quality, lesion conspicuity, and ability to help differentiate solid lesions from hemangiomas. RESULTS: All half-Fourier RARE images were free of respiratory artifact. In the 48 patients with 102 focal lesions, CT, half-Fourier RARE, and multishot RARE images depicted 101, 99, and 90 lesions (99%, 97%, and 88%), respectively. CT failed to depict focal lesions in one patient with diffuse metastatic liver disease. All techniques had high accuracy for distinction of hemangiomas from solid masses (areas under the receiver operating characteristic curves were between 0.96 and 0.99). CONCLUSION: Half-Fourier RARE MR imaging is a rapid and accurate technique for detection and characterization of focal liver lesions.