In this chapter, a comprehensive review of devices intended for use in pulmonary inhalation was introduced, from both historical context and technical perspective. Inhalation devices are of three main types, which are pressurized metered dose inhalers (pMDIs), dry powder inhalers (DPIs) and medical nebulizers. For DPIs, the role of carrier was discussed and the need for active inspiration of the patient was emphasized. For pMDIs, the significance of transition from the ozone-depleting chlorofluorocarbon propellants to the environmentally safer ones, namely hydrofluoroalkanes (HFAs), was reported. Medical nebulizers were discussed in terms of their subtypes and benefit using traditional solutions or dispersions of the medication. Recently, many researchers have considered soft mist inhalers (SMIs) as an additional category of inhalation devices, whilst others may consider it a nebulizer-like device taking into account it delivers liquid formulations; thus, we also reviewed SMIs.