In low and lower-middle income countries most children will reach the ‘end of primary-school age’ without having learned basic skills. The situation often worsens in secondary schools. Teaching quality is the most important factor in determining student learning outcomes, yet despite massive investment in teacher education, many teachers remain poorly prepared to address learners needs, regardless of whether they are fully trained, un- or under-trained. The UK Department for International Development (DFID) Education Policy 2018, in alignment with other donors, will support national efforts to “overhaul out-dated models of teacher training, drawing on evidence-based approaches to improve teachers’ skills which deliver for children, including those who are poor and marginalised”. Particular importance is given to “practical experience in the classroom and ongoing school-based support”. In this paper we seek to set-out a succinct summary of the evidence-base on effective approaches to improving teaching quality for the children of poor and marginalised communities, before practically considering how such evidence-based approaches are manifest across different programmes from Bangladesh and India, to Palestine and Zimbabwe. We provide a starting point for those wishing to understand, emulate or adapt such programme designs, by illustrating ‘how’ school-based support and open-learning have been used to improve teaching quality across a range of settings. Further in-depth practical advice is provided to those wishing to explore School-Based Teacher Development (SBTD) programme design and development, through the COL SBTD Blueprint and Toolkit (Moon, 2018). // Paper ID 256