This study investigated the characteristics of families with a new baby, screened to identify families with vulnerability, who did not take up the offer of home-visiting support from a community volunteer. Using logistic regression, background factors were compared with those families receiving support. Those not receiving support, 59.1% of those referred, were more socially, educationally and economically disadvantaged, living in more disadvantaged neighbourhoods. Those who received support were more likely to have larger families, no local support network, or had family members with health or mental health problems. One in nine families referred had not been reached by the support service. In brief qualitative telephone interviews, mothers who did not take up the offer of support reported changing their mind, wanting to cope without help and in some cases feeling that the support offered did not meet their specific needs. Policy implications are suggested, in particular offering support to new parents thought to be vulnerable within a statutory framework, with sufficient infrastructure and resources to conduct outreach work. Research implications include making a concerted effort to find out about families who decide not to take part in service evaluation studies, or who drop out after initial agreement.