Sexual dysfunctions and sexual problems are reviewed from the perspective of prevalence, broad etiological factors, and available treatments. Although a large percentage of individuals experience sexual problems, with estimates between 10 and 52% of men and 25 and 63% of women, the prevalence of sexual dysfunctions that meet diagnostic criteria is lower and less well established by large scale population-based studies. Sexual problems and dysfunctions are correlated with other health conditions, including cardiovascular disorders, common diseases such a s diabetes, health habits, and mental health. Adequate sexual functioning also appears to be associated with personal well-being and relationship stability, although this may be more accurate for men than women. Efficacious and effective treatments exist for some of the sexual disorders, and there is an increasing focus on medical (particularly pharmacological) treatments being tested by the pharmaceutical industry. Sexual problems and dysfunctions have been notably under-researched, particularly from the perspective on consequences to individual mental health, relationships, and family functioning.