Several computer-aided tools could be used to support a broad area of architectural design. The intention of this paper is to give an overview of possible tools that support the analysis, synthesis, or evaluation processes underlying architectural design. We evaluate these tools and elicit their requirements as tools for computer-aided architectural design. Potential improvements are a broadening of the solution-space of the architect (stimulate inspiration), an increasing speed or ease of generating and evaluating design alternatives, a better accessibility of required information, and verification of the rules and demands of the brief. In developing a tool for the very early design stage, an overview of existing tools, including their potential advantages and drawbacks, that could somehow support these ideas is a necessary stepping-stone.