In the present study, the effects of teachers' beliefs and practices about writing pedagogy on students' progress were investigated in the context of the New Zealand primary school system. A total of 626 teachers completed a survey on their beliefs and practices. Principal component analysis of beliefs isolated three dimensions, reflecting valuation of (i) explicit, (ii) socio-cultural and (iii) process-writing approaches. Analysis of the practices data isolated six dimensions: (i) explicit and structured approaches; (ii) socio-cultural and process writing approaches; (iii) attention to surface features; (iv) advanced writing practices; (v) basic writing practices, and (vi) teacher goal selection. Next, a sub-sample of 19 survey respondents supplied writing samples from their students, at two time points, allowing for the measurement of progress over time. Associations between teachers' scale locations for reported beliefs and practices, and their students' progress were explored. Explicit teaching beliefs and practices were positively correlated with progress and socio-cultural practices were negatively correlated with progress. Our findings support the use of explicit methods for the teaching of writing and cast some doubt over the efficacy of constructivist approaches.