Sexually transmitted diseases (STDs) are contagious diseases which are transmitted from one partner to the other through various forms of sexual contact. It is estimated that more than 400 million people per year get infected by some sexually transmitted disease. The high-risk population consists of adolescents, women of reproductive age and infants born to infected mothers. Classic STDs like gonorrhea and syphilis are less frequent today than viral and chlamydial diseases. Sexually transmitted diseases are of high medical significance. HPV infections of high oncogenic potential are high-risk factors for the development of premalignant changes and cervical carcinoma. HSV type 2 is highly contagious and causes most genital infections. HIV causes a disease which represents a chronic progressive process and starts with the entrance of the virus into the bloodstream and in time leads to a completely destroyed immune system. AIDS is an aquired immune deficiency syndrome which is caused by the HIV virus. The hepatitis B and C viruses causes accute and chronic inflammation of the liver and the chronic stage can lead to cirrhosis and hepatocellular carcinoma. Chlamydia trachomatis is the most frequent sexually transmitted bacterium which is mostly manifested as mucopurulet cervicitis or urethritis. Treponema pallidum is the causative agent of syphilis and is divided into the primary, secondary and tertiary stage. Gonorrhea is a rare sexually transmitted disease which is manifested as cervicitis or urethritis. Trichomonas vaginalis is among the most frequent causative agents of vulvovaginitis. Pelvic inflammatory disease (PID) can occur due to the ascending spread of micro-organisms from the lower parts of the reproductive system. Later complications of PID are ectopic pregnancy, chronic pelvic pain and infertility. The best method for controlling this group of diseases is prevention through education about sexually transmitted diseases, responsible sexual behaviour, detection of asymptomatic patients and vaccinations. Prevention should be an integral part of a comprehensive system of health care services focused on the sexual and reproductive health.