Background: Over the past 25 years, researchers have performed >120 randomized controlled trials (RCTs) illustrating short courses to be non-inferior to long courses of antibiotics for common bacterial infections. Objective: We sought to determine whether clinical data from RCTs affirm the mantra of ‘shorter is better’ for antibiotic durations in 7 common infections: pneumonia, urinary tract infection, intra-abdominal infection, bacteraemia, skin and soft tissue infection, bone and joint infections, pharyngitis and sinusitis. Sources: Published RCTs comparing short- versus long-course antibiotic durations were identified through searches of PubMed and clinical guideline documents. Content: Short-course antibiotic durations consistently result in similar treatment success rates as longer antibiotic courses among patients with community-acquired pneumonia, complicated urinary tract infections in women, gram-negative bacteraemia, and skin and soft tissue infections when the diagnosis is confirmed, appropriate antimicrobials are used, and patients show clinical signs of improvement. For patients with osteomyelitis, 6 weeks of antibiotics is adequate for the treatment of osteomyelitis in the absence of implanted foreign bodies and surgical debridement. Whether durations can be further shortened with debridement is unclear, although small studies are promising. Implications: With few exceptions, short courses were non-inferior to long courses; future research should focus on appropriately defining the patient population, ensuring the correct choice and dose of antimicrobials and developing meaningful outcomes relevant for frontline clinicians.