Currently, clinical practice guidelines and international guidelines on diagnosis and management of asthma, including special considerations in patients under five years old, given the frequent respiratory morbidity associated with this age group and poor or no cooperation from the child for testing respiratory function, favoring the underdiagnosis, delaying treatment and affecting the proper assessment of severity, level of control, and adequate clinical response to treatment. That is why the proper understanding of the natural history and the different phenotypes in infants and toddlers, allow for functional and clinical considerations on the progression of asthma from early childhood to adulthood, being necessary to make a special deal considering personal and family history, symptoms and progression of comorbidities exist which in turn will classify, monitor and plan treatment to achieve and maintain control of the disease, so far as asthma is not cured but their control is achieved in most patients. The doctor-patient interaction, family, education, control of risk factors and comorbidities, assessment, treatment and monitoring of the development of asthma are the foundation for success in the management of asthmatic patients.