Second trimester abortions constitute 10-15% of all induced abortions worldwide but are responsible for two-thirds of major abortion-related complications. During the last decade, medical methods for second trimester induced abortion have been considerably improved and become safe and more accessible. Today, in most cases, safe and efficient medical abortion services can be offered or improved by minor changes in existing health care facilities. Second trimester medical abortion can be provided by a nurse-midwife with the back-up of a gynaecologist. Because of the potential for heavy vaginal bleeding and serious complications, it is advisable that second trimester terminations take place in a health care facility where blood transfusion and emergency surgery (including laparotomy) are available. This article provides basic information on regimens recommended for second trimester medical abortion. The combination of mifepristone and misoprostol is now an established and highly effective method for second trimester abortion. Where mifepristone is not available or affordable, misoprostol alone has also been shown to be effective, although a higher total dose is needed and efficacy is lower than for the combined regimen. Therefore, whenever possible, the combined regimen should be used. Efforts should be made to reduce unnecessary surgical evacuation of the uterus after expulsion of the fetus. Future studies should focus on improving pain management, the treatment of women with failed medical abortion after 24 hours, and the safety of medical abortion regimens in women with a previous caesarean section or uterine scar.