The Infectious Diseases Society of America (IDSA) has issued updated guidelines for the management of community-acquired pneumonia (CAP) in adults. These guidelines, revised in 2000 and updated every 6–12 months, provide recommendations categorized by strength (A–D) and evidence quality (I–III). Chest radiography is critical for diagnosing CAP and distinguishing it from acute bronchitis. Patients are stratified into five risk classes based on age, comorbidities, and clinical findings. Those in risk classes I and II typically do not require hospitalization, while classes III, IV, and V usually do. Laboratory tests, including chest radiography, blood cultures, and sputum analysis, are recommended for hospitalized patients. Antimicrobial therapy is tailored to the etiologic diagnosis, with options including macrolides, doxycycline, or fluoroquinolones for outpatients and broader regimens for hospitalized patients. The IDSA recommends using the Pneumonia PORT prediction rule to guide hospitalization decisions, which has been shown to reduce unnecessary hospitalizations. The most common causes of CAP are Streptococcus pneumoniae and Legionella. Prevention strategies include vaccination against influenza and pneumococcal disease. Diagnostic evaluation includes chest radiography, Gram staining, and culture of sputum. The guidelines emphasize the importance of establishing an etiologic diagnosis to guide targeted antimicrobial therapy and improve patient outcomes. The role of specific pathogens varies, with some causing CAP more frequently in certain populations. The guidelines also highlight the need for further research to validate the use of prediction rules in outpatient settings. Overall, the IDSA guidelines aim to improve the management of CAP through evidence-based practices, reducing unnecessary hospitalizations and antibiotic use while ensuring appropriate treatment for high-risk patients.The Infectious Diseases Society of America (IDSA) has issued updated guidelines for the management of community-acquired pneumonia (CAP) in adults. These guidelines, revised in 2000 and updated every 6–12 months, provide recommendations categorized by strength (A–D) and evidence quality (I–III). Chest radiography is critical for diagnosing CAP and distinguishing it from acute bronchitis. Patients are stratified into five risk classes based on age, comorbidities, and clinical findings. Those in risk classes I and II typically do not require hospitalization, while classes III, IV, and V usually do. Laboratory tests, including chest radiography, blood cultures, and sputum analysis, are recommended for hospitalized patients. Antimicrobial therapy is tailored to the etiologic diagnosis, with options including macrolides, doxycycline, or fluoroquinolones for outpatients and broader regimens for hospitalized patients. The IDSA recommends using the Pneumonia PORT prediction rule to guide hospitalization decisions, which has been shown to reduce unnecessary hospitalizations. The most common causes of CAP are Streptococcus pneumoniae and Legionella. Prevention strategies include vaccination against influenza and pneumococcal disease. Diagnostic evaluation includes chest radiography, Gram staining, and culture of sputum. The guidelines emphasize the importance of establishing an etiologic diagnosis to guide targeted antimicrobial therapy and improve patient outcomes. The role of specific pathogens varies, with some causing CAP more frequently in certain populations. The guidelines also highlight the need for further research to validate the use of prediction rules in outpatient settings. Overall, the IDSA guidelines aim to improve the management of CAP through evidence-based practices, reducing unnecessary hospitalizations and antibiotic use while ensuring appropriate treatment for high-risk patients.