The present guideline provides a new and updated concept of treatment and prevention of adult patients with community-acquired pneumonia. It replaces the previous guideline dating from 2009.The guideline was worked out and agreed on following the standards of methodology of a S3-guideline. This includes a systematic literature search and grading, a structured discussion of recommendations supported by the literature as well as the declaration and assessment of potential conflicts of interests.The guideline has a focus on specific clinical circumstances, an update on severity assessment, and includes recommendations for an individualized selection of antimicrobial treatment as well as primary and secondary prevention.