Most current object modeling methods and tools have weaknesses both in the concepts of hierarchical decomposition and in the visualization of these hierarchies. Some methods do not support hierarchical decomposition at all. Those methods which do employ tools that provide explosive zoom as the only means for the visualization of hierarchies. In this paper we present an approach for the visualization of hierarchical object models based on the notion of fisheye views. This concept integrates local detail and global context of a view in the same diagram and eases navigation in hierarchical structures without offending the principle of ion. The work presented here is part of an effort to create a method and language called ADORA that provides strong support for hierarchical decomposition.