A method for massive-model visualization, comprising: a) storing a massive model database for a product data structure in a product data management server system (100, 220) in the following denoted by PDM server system, wherein the product data structure represents a product assembly, including storing a spatial bounding box hierarchy that acts as a spatial index for spatial bounding boxes of a plurality of unconfigured components of the product data structure, wherein an unconfigured component is a component of which several possible different variants exist, and for which the variant is not yet fixed, and wherein the spatial bounding box hierarchy is based on a bounding box of the unconfigured component that contains all variants, and storing a cell table that associates cells of the spatial bounding box hierarchy to corresponding component identifiers of the product data structure; b) transmitting the spatial bounding box hierarchy to a client system by means of the PDM server system (100, 220); c) receiving by the PDM server system (100, 220) from the client system a search cursor that contains a plurality of root nodes of user-selected sub-assemblies represented by the product data structure as represented in the spatial bounding box hierarchy, and a user selected view point; d) determining by means of the PDM server system (100, 220) and based on the spatial bounding box hierarchy and the search cursor, the cells and components that correspond to the search cursor, including performing a search of the product data structure to identify components of each of the sub-assemblies that correspond to the search cursor and determining which of the identified components are visible from said given viewpoint; e) transmitting, by means of the PDM server system (100, 220), component identifiers, for the components determined to be visible, from the product data structure to the client system and f) configuring the product data structure and its components by means of the PDM server system (100, 220), and transmitting, by means of the PDM server system (100, 220) and to the client system, geometric data corresponding to components of the product data structure associated with the component identifiers and according to the configured product data structure, wherein data sent to the client system for display only include configured data; g) wherein the client system uses the transmitted geometric data to display the components of the assembly represented by the product data structure that are determined to be visible from the given viewpoint. a) storing a massive model database for a product data structure in a product data management server system (100, 220) in the following denoted by PDM server system, wherein the product data structure represents a product assembly, including storing a spatial bounding box hierarchy that acts as a spatial index for spatial bounding boxes of a plurality of unconfigured components of the product data structure, wherein an unconfigured component is a component of which several possible different variants exist, and for which the variant is not yet fixed, and wherein the spatial bounding box hierarchy is based on a bounding box of the unconfigured component that contains all variants, and storing a cell table that associates cells of the spatial bounding box hierarchy to corresponding component identifiers of the product data structure; b) transmitting the spatial bounding box hierarchy to a client system by means of the PDM server system (100, 220); c) receiving by the PDM server system (100, 220) from the client system a search cursor that contains a plurality of root nodes of user-selected sub-assemblies represented by the product data structure as represented in the spatial bounding box hierarchy, and a user selected view point; d) determining by means of the PDM server system (100, 220) and based on the spatial bounding box hierarchy and the search cursor, the cells and components that correspond to the search cursor, including performing a search of the product data structure to identify components of each of the sub-assemblies that correspond to the search cursor and determining which of the identified components are visible from said given viewpoint; e) transmitting, by means of the PDM server system (100, 220), component identifiers, for the components determined to be visible, from the product data structure to the client system and f) configuring the product data structure and its components by means of the PDM server system (100, 220), and transmitting, by means of the PDM server system (100, 220) and to the client system, geometric data corresponding to components of the product data structure associated with the component identifiers and according to the configured product data structure, wherein data sent to the client system for display only include configured data; g) wherein the client system uses the transmitted geometric data to display the components of the assembly represented by the product data structure that are determined to be visible from the given viewpoint.