The ConceptBase 5.2.3 Release comprises an integrated, predefined working environment for comfortable tool usage called ConceptBaseWorkbench. This tool was programmed from scratch for the current release and replaces its predecessor, ConceptBase Tool Bar and related tools. ConceptBaseWorkbench pays respect to the many suggestions of ConceptBase users which results in more comfortable and therefore more effective usage of the ConceptBase services. The ConceptBaseWorkbench application provides a number of facilities to manage conceptual models under the X window system, version 11 release 5. The X Window System was chosen to avail a standard ConceptBase working environment to the broad range of machines which support this protocol.