Several electronic nebulizer devices that use a vibrating mesh or plate with multiple apertures to generate a fine-particle, low-velocity aerosol have been marketed or will shortly become available for clinical use. These devices have a high efficiency of delivering aerosol to the lung, such that the nominal dose of drugs to be administered could be substantially reduced. Moreover, the volume of drug solution left in these new devices when the nebulization has ceased is negligible, so there is potential to improve the cost-effectiveness of administering expensive medications. Because these devices nebulize at a faster rate than conventional jet or ultrasonic nebulizers, the duration of each treatment could be shortened. These devices efficiently nebulize solutions and suspensions; they have been successfully used for aerosolizing insulin, other proteins and peptides, and fragments of DNA. They could be employed for a wide variety of clinical applications, including the delivery of aerosols for systemic therapy and gene transfer. These devices have overcome many of the limitations associated with conventional jet and ultrasonic nebulizers, and they offer the versatility to modify the aerosol characteristics according to the clinical application for which they are employed. With these devices clinicians will be able to precisely control drug delivery to the respiratory tract.