This article explores the constructions of communicative openness following adoption. Data from three waves of interviews with six adoptive mothers and four foster carers were collected, transcribed verbatim and analysed in keeping with a social constructivist grounded theory methodology. The results show that the way ‘family’ is constructed can both facilitate and impede communicative openness. Those who hold a fluid, child-centred concept of family, are willing to construct it as different and can accept the ebb and flow of family membership intuitively and view such openness as a natural part of caring for children. Those with a more traditional, nuclear construction of family may associate adoption with fear, a sense of biological related competition and the need to control the controllable, all of which act as barriers to communicative openness. The study demonstrates that communicative openness is person and context sensitive and emphasises the need to think creatively and flexibly about the very nature of family.