Sexually transmitted diseases (STDs) are communicable diseases transferred mainly through sexual contact. With more than 20 pathogens known to be spread by sexual contact STDs are the most common notifiable infectious diseases in most countries. Despite some fluctuation in their incidence STDs continue to occur at unacceptably high levels. For most notifiable STDs the highest rates of incidence are found in 20-24 years olds followed by people aged 25-29 and 15-19. Among sexually active teenagers the highest incidence of STD infection is among the youngest teens. For most STDs the overall morbidity rate is higher for men than for women. STD control programs need to be designed and implemented with the understanding that migration has always been linked with STD. Sexual preference marital status socioeconomic status place of residence prostitution migration principal STDs populations at risk and prevention and control measures are discussed. Strategies to prevent STD transmission must remain flexible in order to adapt to prevailing conditions with adequate clinical services being central in controlling STDs.