Introduction: Taste and smell abnormalities have proven to be an extremely more complex subject than previously regarded. Wide-ranging nosologic entities arise along with smell and taste alterations, and they can be congenital or acquired. Objective: Analyze the main features of smell and taste dysfunctions. Method: Automated databases were used to collect data, by searching keywords like 'alteration', 'smell', and 'taste'. A nonsystematic search was also made in scientific printings and medical books. Literature Review: Smell and taste dysfunctions have a vast etiology, the most significant of which are obstructive nasal and sinusal disease, infections of the upper respiratory tract, cranioencephalic trauma, aging, exposure to toxics and some drugs, nasal or intracranial neoplasias, psychiatric and neurological pathologies, iatrogenic disease, idiopathic and congenital causes. A detailed anamnesis, a careful physical examination and supplementary evaluations are important for the diagnosis of these alterations. Conclusion: As a rule, smell and taste dysfunctions occur in a combined way. The early discovery of such dysfunctions can lead to a more efficient treatment, making the progress of diseases causing them retard and the symptoms less severe. In many cases, treating these alterations is not easy and there needs to be a multidisciplinary cooperation among the otorhinolaryngologist, endocrinologist, neurologist, psychiatrist, among others.