The interactive bi-objective programming with valuable trade off (IBVT) approach to general capacitor placement and scheduling problems is proposed. A novel simulated annealing-like, modified particle swarm optimization (SA-PSO) is also presented and applied for better solution quality. Two main contradictory concerns, which including cost and quality properties, are considered for optimization. For practical needs, the operating and expansion constraints of distribution feeders are formulated. Also, both fixed and switched types of capacitors are included. To demonstrate the effectiveness and feasibility of the proposed method, comparative studies were conducted on an actual feeder systematically. The experiment showed encouraging results, suggesting that the proposed approach was capable of efficiently determining higher quality solutions. (c) 2008 Elsevier Ltd. All rights reserved.