The selection process of architectural patterns is challenging for software architects, as knowledge about patterns is scattered among a wide range of literature. Knowledge about architectural patterns must be collected, organized, stored, and quickly retrieved when it needs to be employed. In this tool paper, we introduce a decision support system that uses a decision model for supporting software architects with the pattern selection problem according to their requirements, including functional and quality requirements. The decision model is built based on a technology selection framework for modeling multi-criteria decision-making problems in software production. Finally, a practical running example is presented to explain the decision model’s use to support software architects with the pattern selection problem. Twenty-four software architects in the Netherlands have evaluated the tool. They confirmed that the tool supports them with their daily decision-making process.