This paper reviews the work and contribution of one of the most influential comparativists in education--Torsten Husén in the period when he was a co-founder and chairman of the International Association for the Evaluation of Educational Achievement (IEA) in the 60 and 70 decades of the 20th century. At that particular time, the first major cross-national and widely reported IEA surveys were carried out. The author places special emphasis on the exemplary First International Mathematics Study (FIMS), which "presents the results of the first completed survey of the achievements of thirteen-year-olds, pre-university mathematics and nonmathematics students in twelve countries" (Eckstein, 1977). As a result, the IEA initial studies revolutionized the reality of Comparative Education as a scientific field and an academic discipline in a way that it proved that such research was completely feasible. [For the complete Volume 13, Number 1 proceedings, see ED568595.]