The enterprise architectures goal is to integrate business resources and IT resources in order to improve an enterprises competitiveness. Our goal is the development of an object-oriented enterprise architecture method, called "SEAM". As part of SEAM, we have developed the CAD tool "SeamCAD". SeamCAD enables the modeling of hierarchical systems (spanning from business down to IT) at different levels of detail (e.g. from large business transaction to detailed interactions). This document is the users guide of SeamCAD 1.x. It first gives an overview of the foundations of our method and then illustrates the functionalities of the tool.