This disclosure relates to a method and system for automatically generating selection conditions associated with component variants represented in a hierarchical node structure in a product configuration system. The selection conditions relate to a determination of when component variants are to be included in a configurable product. The method and system may involve receiving relationship information for component variants at a first node level of the node structure, and determining what combinations may be formed from the component variants based on the relationship information. The method and system may further involve forming assembly variants corresponding to the combinations, at a second node level higher than the first node level, and forming selection conditions corresponding to the assembly variants based on selection conditions corresponding to the component variants.