There is a delicate balance between the benefits and harms of mammography screening, and women should decide for themselves, on an informed basis. The invitation to have a mammography is the only source of information provided to all eligible women, and we explored whether it provides such a basis. We collected invitations from English-speaking and Scandinavian countries. The major benefit of screening, a reduction in breast cancer mortality, was mentioned in 30 of 31 invitations, whereas the most important harms, overdiagnosis and overtreatment, were not mentioned in any of the invitations.