Electronic commerce demands appropriate reorganization of business processes made in conjunction with the introduction of powerful information systems. There are numerous already-proven concepts from business management and information systems that can be partly relied on. There is, however, a series of specific demands that must be accounted for in the design of specialized systems. The following article is directed at object-oriented modeling of products that are offered on e-commerce websites. Unlike traditional inventory management, products traded on e-commerce websites are often not fully recognized at the time when the system is constructed. Instead there is the need to register new product types during the run time of a system. In addition, the representation of product variants and the construction of individual product configurations should be possible. Motivated by a series of additional demands to be leveled at systems such as this, two obvious modeling approaches will be described first. A powerful approach will then be mapped out, which is based in part on the use of meta concepts. This approach originated within the design of a reference model for e-commerce platforms on the Internet.