Behaviour and psychosocial adjustment are impaired in children with steroid-sensitive idiopathic nephrotic syndrome (SSNS). Both illness-related variables and family climate play a role. Steroid treatment-both short- and long-term-is an important contributor among other determinants. The exact mechanisms by which steroids lead to behavioural alterations in humans is unclear. Optimizing the benefit/risk ratio of steroid treatment in children with SSNS is a constant goal.