When a mission-critical application fails, the loss of business revenue is large and swift. Poor application quality causes highly-visible major outages; it also causes ongoing lapses in business performance thatare less visible, but steadily add up to substantial revenue loss. Even minor quality improvements can result in significant business gain. Yet, executives struggle to build a business case to justify proactive investments in application quality. This paper presents a quantitative framework for measuring the immediate and positive revenue impact of improving application quality.