Focal therapy for prostate cancer has been increasingly utilized with the goal of effective disease control while maximizing patient functional outcomes. The optimal patient selection criteria are not known and therefore are not standardized. This review compares the available expert panel consensus guidelines with the selection criteria utilized in recently published focal therapy trials. Because the data from focal trials are still maturing, the currently enrolling clinical trials are reviewed as well. In addition, the recent literature regarding technological advances in prostate biopsy and imaging strategies are added to the current guidelines to recommend a rationale for patient selection.