While component-based software engineering technologies have become popular, finding and reusing appropriate software components is often challenging. We describe a software component repository that uses a concept of component "aspects" to index and query components based on their high-level systemic characteristics, including their user interface, persistency, distribution, security and collaborative work support. Software components are queried for aspects of a system they provide or require and these are used to automatically generate a high-level indexing system. Developers and end users can formulate high-level, aspect-based queries to retrieve components providing or requiring services appropriate to their needs.