Peter J. Rossi, MD, a radiation oncologist with Kaiser Permanente and Valley View Hospital in Glenwood Springs, Colorado, and Steven J. Frank, MD, a professor of radiation oncology at the University of Texas MD Anderson Cancer Center, present important updates on brachytherapy for the treatment of prostate cancer. Dr. Rossi notes that radiationresistant tumors can be treated with wellexecuted brachytherapy, and highlights the levelone evidence for prostate brachytherapy over other treatments. He also discusses some drawbacks to brachytherapy, particularly toxicity, and how they can be addressed. Dr. Frank follows, discussing MRIassisted radiosurgery (MARS) and highlighting the strengths of MRI over CT scans and ultrasounds in brachytherapy. He also outlines the findings of a study he led regarding the use of MRIassisted brachytherapy, emphasizing that the quality of MRI imaging allows for higher quality of care and largely avoids the problem of toxicity. Dr. Frank also discusses the difference between MRIguided and MRIassisted therapy, and highlights important steps to avoid certain negative outcomes.