Inhaled antimicrobial therapy is attractive because of its potential to provide high concentrations of antimicrobials to the site of active respiratory infections while avoiding systemic toxicity. Many antimicrobials have been used in inhaled preparations, including aminoglycosides, colistin sodium, cephalosporins, penicillins, vancomycin, amphotericin B, and several antiviral compounds. This review highlights available data on inhaled antimicrobials, antifungals, and antivirals for the prevention and treatment of infections of the respiratory tract.