The development of urinary symptoms after brachytherapy is very frequent, reaching a maximum between the first and third month after the implant and returning back to normal around one year. The incidence of acute urinary retention varies between 1.5 and 27% . A low percentage of patients (0-8.7% ) will need surgery to solve an extended urinary retention or severe obstructive voiding symptoms. Alphablockers may be useful to alleviate voiding symptoms after the implant, although they do not reduce the need for surgery. There are several predictive clinical factors for development of urinary complications. A patient with high IPPS score before implant, large size prostate, obstructive functional signs (Low Q max, high postvoid residual, and obstruction urodynamic parameters) has a high risk for urinary retention or extended urinary symptoms. This has repercussion on the quality of life of the patient, making them candidates to other therapies. The performance of a peripheral implant technique (guaranteeing low doses at urethra) and avoiding the urethral plane when inserting the needles may minimize urethral damage associated with development of urinary complications. Urinary incontinence after brachytherapy is a rare complication, but its frequency increases dramatically after transurethral resection of the prostate or requiring it to solve a sustained urinary retention. It is fundamental to know this circumstance to inform the patient adequately and to plan the most careful TURP.