Urinary incontinence, an uncontrolled urine leakage during the storage phase of micturition, is a common condition in female dogs. In intact bitches, the reported prevalence is only 0.2-0.3%, but in spayed bitches it varies between 3.1-20.1%. Most commonly, dogs with acquired urinary incontinence suffer from urethral sphincter mechanism incompetence. This condition seems to be multifactorial, and although the exact pathophysiology remains unclear, potential risk factors include gender, gonadectomy, breed, body weight, urethral length and bladder neck position. In daily practice, the diagnosis of urethral sphincter mechanism incompetence is usually made after eliminating other potential causes of urinary incontinence. Incontinent bitches are primarily treated with medications, such as alpha-adrenergic drugs, e.g. phenylpropanolamine and oestrogens. Surgery is recommended when patients become refractory to medical treatment.