Interstitial cystitis, or painful bladder syndrome, is a condition characterized by bladder pain, urinary frequency, urgency, and nocturia. The cause of the condition remains obscure and it remains a diagnosis of exclusion. Current theories of pathogenesis include a chronic or subclinical infection, autoimmunity, neurogenic inflammation or bladder urothelial defects. The definitions and terminology have undergone several proposed changes in the last five years. The International Incontinence Society (ICS) provided a revised definition of painful bladder syndrome (PBS) in 2002. The European Society for the Study of Interstitial Cystitis (ESSIC) proposed a new nomenclature, "bladder pain syndrome", and classification system in 2008 for the same condition. Treatment strategies can be categorized broadly into four different approaches: (i) intravesical drug instillation, (ii) systemic (oral) medical therapy, (iii) administration of local treatments, and (iv) surgical procedures for refractory disease. Intravesical drug instillation or oral therapies are the mainstay of treatment.