The campaign asks people to commit to a monthly £3 donation by direct debit. It features a family, one of whom has cancer, and explains the charity's work. The message is that Macmillan helps both cancer sufferers and their families.
A freephone number appears throughout the 90-second ad, which was created by agency Different Kettle. It is being aired on satellite and cable channels including UK Horizons, Granada Plus and ITV News.