This　paper　presents　a　case　study　for　the　advanced　planning　and　scheduling　(APS)　problem　encountered　in　a　light　source　manufacturer.　The　APS　problem　explicitly　considers　due　dates　of　products,　operation　sequences　among　items,　and　capacity　constraints　of　the　manufacturing　system.　The　objective　of　the　problem　is　to　seek　the　minimum　cost　of　both　production　idle　time　and　tardiness　or　earliness　penalty　of　an　order.　An　intelligent　heuristic　is　applied　to　the　problem,　and　the　results　demonstrate　that　significant　production　performances　can　be　achieved　while　ensuring　customer　satisfaction　as　opposed　to　normal　practices　followed　in　the　company　relying　on　human　expertise.