The production of insulating glass and curtain wall involves the use of adhesives and sealing steps to join multiple parts. The success of these steps requires accurate dispensing and proper mixing of adhesive components. Generally, a proportioner is used to achieve adhesive mixing. However, this equipment does not have real-time ratio control. A small mixing error can result in complex cleaning procedures. Cleaning after shift changes or for a material change can be similarly time consuming. Recent advances in adhesive proportioners address many of the drawbacks of this equipment. Ration assurance is a challenge with traditional proprotioners, but digital systems have drastically improved monitoring and operator control over mixing ratios. Real-time monitoring and adjustment can avoid many mixing errors. In addition, real-time systems can be equipped with fail-safes that stop the system if there is off ratio mixing. Tested pump technology, specialized hoses, and other equipment improvements have extended the life and reduced maintenance costs on newer equipment. Overall, new proportioners are more precise, accurate, durable and cost-effective to operate.