Selective termination in twin pregnancies with a chromosomal abnormality in one twin may be offered to prevent long-term suffering for the infant and/or the family. The procedure poses considerable risks to the remaining fetus and also to the mother, and these, together with the ethical aspects, should be discussed thoroughly with the couple. We report 2 successful cases of selective midtrimester termination by intracardiac potassium chloride injection, and recommend a management protocol for selective birth in twins with discordant chromosomal abnormalities.