In Cambodia, just over four per cent of the population aged 6-14 and two and a half per cent of the population aged 15-24 have never attended school; in addition, dropout also remains an issue. To provide a second chance for these groups, the Cambodian Ministry of Education, Youth and Sport (MoEYS) established an equivalency programme (EP), at primary, lower secondary and upper secondary levels. Primary-level EP, the focus of this article, was launched in 2015 and offers access to flexible learning for out-of-school children, youth and adults. However, up to now, there is very little information on the effectiveness of the programme. The mixed methods study presented here aimed to examine programme outcomes in terms of learners' knowledge and skills, their attitudes, their practical application of acquired skills, and major factors influencing learners' learning outcomes. The author surveyed and assessed 96 EP learners' learning outcomes and interviewed nine equivalency teachers and two non-formal education officers. His findings show that while EP curriculum contents were relevant, they are still in need of revision. Equivalency teachers' own low educational background and insufficient teacher training lead to low teaching performance; and consequently to EP learners' low test scores or poor learning achievement. The author identifies three factors significantly associated with learners' learning achievement: (1) the classroom learning environment; (2) instructional practices; and (3) learning assessments that reflect classroom contexts. Among these, he found instructional practice to have the greatest influence on learning achievement. Based on these findings, the author stresses there is an urgent need for increasing attention on improving equivalency teacher quality and curriculum.