The importance of sleep on health has only been recently recognized, and the general public and the medical community are not yet fully knowledgeable about this issue. The great majority of sleep research has been performed in whites of European descent and to a lesser extent in African Americans, making generalization of the findings to other ethnic and racial groups difficult. Very little sleep research has been done in U.S. Hispanics. However, based on the available literature and the high prevalence of risk factors in Hispanics, such as obesity, diabetes, living in the inner city, and use of alcohol, the prevalence of such important sleep disorders such as obstructive sleep apnea and sleep habits such as poor sleep hygiene are suspected to be high. There is also some evidence that acculturation to the U.S. life style may lead to worse sleep habits in Hispanics, including fewer hours of sleep. Two current large NIH sponsored studies of sleep in U.S. Hispanics promise to significantly add to the literature on various sleep disorders such as sleep disordered breathing, insomnia, restless legs syndrome, periodic limb movement disorder, and sleep habits such as short sleep duration and sleep hygiene.