There are multiple well-recognized environmental factors that contribute to asthma exacerbation. Exposures to many of them will get unrecognized and most of the time will remain constant without knowing it is the causative agent. For an early identification of exposures and causative agents, a systematic approach needs to be taken in consideration by the encountering physician. Multiple questionnaires had been implementing and discussing organic and inorganic factors as well intrinsic and extrinsic factors. It is well-recognized that environmental exposures can cause worsening of asthma, other allergic conditions and even more severe pulmonary diseases. Asthma is a very prevalent disease with increased incidence nowadays. In the last decade, multiple new medications had been discovered for the treatment of moderate-to-severe persistent asthma, which most of them target the cellular component of the disease such as eosinophils and specific Immunoglobins. In the era of personalized medicine, environmental and occupational factors in asthma are key players that need to be recognized early in this patient population. In this chapter will go over model of effects, mechanism of action of these environmental factors, recognition, course of action and management of this patient population.