<b><i>Background:</i></b> Across Europe, poor health behaviours are associated with increased risks of non-communicable diseases. There is particular concern about young women, children and families, not least as health behaviours operating before and during pregnancy and in early postnatal life may have profound long-term consequences for children's health. Using findings drawn from 7 European countries, we aimed to identify barriers to the implementation and uptake of dietary and physical activity recommendations, and to consider how best to achieve changes in mothers' behaviours and thereby improve the adoption of health recommendations. Six studies across the 7 countries were used for this narrative synthesis of findings. <b><i>Key Messages:</i></b> A woman's education has a strong influence on her own and her children's health behaviours. Women's diets vary across ethnic groups and according to number of children, but psychological factors, such as self-efficacy and sense of control, which may be amenable to modification, are powerful, too, particularly in women with lower educational attainment. Maternal influences on children's behaviours are strong. Differences exist in infant feeding across countries, and there are apparent urban/rural differences in children's diets and physical activity. <b><i>Conclusions:</i></b> Interventions are needed before, as well as during, pregnancy to improve the diets of families with young children. Interventions to address psychological barriers to eating well and being more active are indicated.