Botulinum toxins (BT) are one of the most powerful poisons in nature. They are responsible for human botulism and constitute a potential chemical weapon, but can also be used as a therapeutic agent. Sphincter, bladder and prostatic injections have been described in urological indications as varied as detrusor-sphincter dyssynergia and neurogenic detrusor hyperactivity, idiopathic overactive bladder symptoms, interstitial cystitis, obstructive voiding disorders related to benign prostatic hyperplasia or chronic prostatitis, and recurrent urethral stricture. This review of the literature presents the results and level of evicence in support of the use of BT in urological indications. Detrusor injections of BT-A constitute an alternative conservative treatment that is effective in the short term (6-12 months) after failure of anticholinergic agents to treat neurogenic detrusor hyperactivity (level 1b). Sphincter injections are effective in the short-term treatment of neurogenic detrusor-sphincter dyssynergia (level 1c). The efficacy observed during preliminary clinical trials of detrusor injections of BT-A for idiopathic overactive bladder symptoms or interstitial cystitis (level 4) and prostatic injections for obstruction related to BPH (level 1c) justifies the major interest raised by this new therapeutic approach. However, these preliminary results must be confirmed by comparative studies on a sufficient number of patients with long-term follow-up before considering the use of this technique in routine clinical practice.