The Global Education Monitoring Centre of the Australian Council for Educational Research (ACER GEM) has initiated the development of a set of learning metrics, with the intention of developing a means of measuring and reporting on learning outcomes that will support the Post-2015 development goals. Initial activity was through what was referred to as the Learning Metrics Partnership (LMP), which was explored as a joint initiative of the UNESCO Institute for Statistics and ACER-GEM. The objective is to develop a set of nationally and internationally comparable learning metrics in mathematics and reading, and then facilitate and support their use for monitoring purposes, in partnership with interested countries. The empirically derived learning metrics will support national governments to effectively measure and monitor learning outcomes for policy purposes. This would not involve the development of a new test or testing program. Rather, it would support the use of existing assessments of various kinds (including citizen-led, regional and national assessments), and a pool of calibrated items that could be used to facilitate measurement and reporting of local learning outcomes against common metrics. A key output of this work would be a common learning metric for reading, spanning reading development from early primary school to early secondary school. In the conceptualisation of the reading metric, comprehension is represented as the central developmental continuum, with other components of early reading mapped differentially in relation to comprehension according to the linguistic specificities of different languages.