Routine cardiovascular imaging has dramatically increased over the last 2 decades across demographic subgroups, with marked variation in regional- and hospital-based utilization. This rapid growth and excess cost expenditure cannot be fully accounted for by changing disease rates, and it has not consistently translated into improved patient outcomes. Based on international comparative data, there is a clear disconnect between diagnostic testing frequency and clinical outcomes. In patients with low-risk non–ST-elevation acute coronary syndromes, enrolled in an international trial, stress testing was more commonly performed outside versus inside the United States, despite a lack of difference in mortality at 30 days, 6 months, and 1 year across geographical regions. Inappropriate routine testing may increase radiation exposure, false positive results, patient anxiety, downstream invasive testing, and unnecessary interventions. Efforts to better delineate appropriateness of cardiovascular diagnostics in various settings often are limited to initial encounters. Clinical decision-making regarding subsequent or serial testing is highly variable. For example, number of echocardiograms performed in a well-monitored cohort of patients with ambulatory heart failure (HF) varies widely from 1 to 30 during a span of only 3 years between the initial and final testing. Large variation in testing frequency across the United States regions suggests lack of clear guidance regarding appropriate testing intervals. For routine re-evaluation of chronic cardiovascular conditions, a test should only be performed as frequently as necessary to detect a clinically meaningful change.