This SHEA Position Paper discusses the importance of diagnostic stewardship in improving patient outcomes and healthcare-associated infection (HAI) metrics. Diagnostic stewardship involves managing the ordering, collection, performance, and reporting of diagnostic tests to enhance the diagnosis and treatment of infections. The paper emphasizes that inappropriate testing should be discouraged, and approaches that solely aim to impact reportable metrics should be avoided. HAI definitions should be adapted to new testing technologies, focusing on actionable and clinically relevant test results. The paper highlights the impact of diagnostic stewardship on HAI rates, particularly for catheter-associated urinary tract infections (CAUTI), hospital-onset Clostridioides difficile infection (HO-CDI), and central-line-associated bloodstream infection (CLABSI). It discusses how diagnostic stewardship can reduce inappropriate testing, improve accuracy in HAI diagnosis, and reduce misclassification of colonization or contamination as infections. The Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN) tracks HAIs, and the paper outlines examples of diagnostic stewardship strategies for NHSN-reportable HAIs. The paper also addresses the challenges and opportunities in leveraging diagnostic stewardship for HAI reduction while maintaining a focus on patient outcomes. It discusses the impact of diagnostic stewardship interventions on HAI prevention, including reductions in testing, HO-CDI reportable cases, and financial savings. The paper emphasizes the need for patient-centered diagnostic stewardship, which focuses on optimizing urine cultures and reducing antibiotic use, while avoiding the potential harms of indiscriminate reductions in urine culturing. The paper also discusses the revision of HAI definitions to better distinguish between clinical infection and colonization, and the impact of these changes on HAI rates. It highlights the importance of adapting surveillance definitions to focus on events that contribute to patient harm and to ensure the sustainability of diagnostic stewardship interventions. The paper concludes that diagnostic stewardship aligns with patient quality and safety goals and that HAI definitions should consider additional clinical criteria, such as the decision to start treatment for the infection, to improve patient outcomes.This SHEA Position Paper discusses the importance of diagnostic stewardship in improving patient outcomes and healthcare-associated infection (HAI) metrics. Diagnostic stewardship involves managing the ordering, collection, performance, and reporting of diagnostic tests to enhance the diagnosis and treatment of infections. The paper emphasizes that inappropriate testing should be discouraged, and approaches that solely aim to impact reportable metrics should be avoided. HAI definitions should be adapted to new testing technologies, focusing on actionable and clinically relevant test results. The paper highlights the impact of diagnostic stewardship on HAI rates, particularly for catheter-associated urinary tract infections (CAUTI), hospital-onset Clostridioides difficile infection (HO-CDI), and central-line-associated bloodstream infection (CLABSI). It discusses how diagnostic stewardship can reduce inappropriate testing, improve accuracy in HAI diagnosis, and reduce misclassification of colonization or contamination as infections. The Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN) tracks HAIs, and the paper outlines examples of diagnostic stewardship strategies for NHSN-reportable HAIs. The paper also addresses the challenges and opportunities in leveraging diagnostic stewardship for HAI reduction while maintaining a focus on patient outcomes. It discusses the impact of diagnostic stewardship interventions on HAI prevention, including reductions in testing, HO-CDI reportable cases, and financial savings. The paper emphasizes the need for patient-centered diagnostic stewardship, which focuses on optimizing urine cultures and reducing antibiotic use, while avoiding the potential harms of indiscriminate reductions in urine culturing. The paper also discusses the revision of HAI definitions to better distinguish between clinical infection and colonization, and the impact of these changes on HAI rates. It highlights the importance of adapting surveillance definitions to focus on events that contribute to patient harm and to ensure the sustainability of diagnostic stewardship interventions. The paper concludes that diagnostic stewardship aligns with patient quality and safety goals and that HAI definitions should consider additional clinical criteria, such as the decision to start treatment for the infection, to improve patient outcomes.