This report presents findings from an ongoing research project monitoring the impact of the Advanced Subsidiary (AS) and Advanced (A) level reforms in England that came into effect from September 2015. Three studies were conducted in the spring of 2017, during the second year of teaching of decoupled AS and A levels. The first study analysed national entries and results data, in order to look at changes in the provision and uptake of AS and A levels. In the other two studies, surveys were conducted of Year 12 and 13 students and Heads of Department to further investigate the provision and uptake of AS and A levels, and, particularly, to further understand the reasons behind student and centre decisions. Among the key findings are: (1) Steep decreases in AS level uptake occurred in the first and second years of teaching decoupled AS and A levels; (2) Analysis of provision identified two main centre responses to the AS/A level reforms: either maintaining pre-reform patterns of entry, or reducing AS provision almost entirely. A partial reduction in AS provision was less common; and (3) Year 12 AS level candidates in 2015/16 were far more likely than those in the previous cohort to be taking only 1 or 2 AS levels, and to be taking AS levels only in non-reformed subjects. Survey data confirmed that many students were taking decoupled A levels without the corresponding AS level.