Adopting a comparative perspective to address educational issues in different contexts was a hallmark of Jullien's work in the early-nineteenth century. Different emphases and approaches to comparative education methodology have emerged in recent times thanks to major developments in technology, but have these changes rendered Jullien's ideas redundant? This paper looks at the current predominant methodology in comparative studies of curriculum by critiquing the instruments of the Programme for International Student Assessment. Some pitfalls of comparing through a focus on student learning outcomes in defined subjects are discussed. The paper concludes by looking at how Jullien's Plan might offer ways of addressing some of the modern challenges and opportunities facing comparative research methodology in curriculum studies.