The implementation processes associated with a home-based phonological awareness intervention were observed for mothers and their 4-year-old children with specific language impairment (SLI). Mother-child dyads (n = 13) read books four times per week over 12 weeks; each book contained nine embedded phonological awareness (PA) tasks. Four hundred and ninety-eight book reading sessions were coded for three variables of interest: maternal support of concept development, quantity of maternal instructional support, and accuracy of children's responses to the PA tasks. Using growth curve modelling, results indicate that maternal support of concept development decreased over the course of the 12-week program, and the quantity of maternal supports changed considerably reflecting intra-individual differences among mothers. Both support of concept development and quantity of support decreased over the course of a given week. In addition, children's responses to the phonological awareness tasks significantly increased over the 12-week intervention. Overall, mothers did not provide support that consistently supported children's learning over time, and the increases in children's correct responses, although significant, were less than anticipated given the length of the intervention. These findings indicate that mothers may need additional supports when implementing emergent literacy programs with their children.