Marketing campaigns and content require messaging that resonates with the intended audience. B2B portfolio marketers must use a mix of intuitive assessments and hard data to ensure that the messaging they create resonates with buyers and helps the organization meet marketing and business objectives. This requires a deep understanding of the buying audience, a disciplined workflow process, and a messaging blueprint that can be used for content and campaign creation. In this report, we present four metric classes for measuring messaging effectiveness: activity; output; impact; and operations and readiness.