Up to now most of the existing water supply network analyses have been based on demand-driven simulation models. These models assume that nodal outflows are fixed and are always available. However, this method of simulation neglects the pressure-dependent nature of demand that is characterized by changes in actual nodal outflows particularly during critical events like major mechanical or hydraulic failures including local excessive demands. A novel approach is presented herein for head-driven simulation of water distribution networks. The methodology is based on the Newton-Raphson method and incorporates, directly, the relationship between nodal outflows and pressures. Through several examples, the applicability and advantages of this new formulation are demonstrated including accuracy and computational efficiency.