Generation-set systems are seldom accepted as full-fledged socio-political systems, and the fact that they are often subsumed under the category of age only increases the likelihood that they are misunderstood. Another aspect that is often overlooked in this context is the role of generational alternations. This paper aims to explore Ateker generation-sets and show how they are socio-political systems sui generis. They reflect and at the same time organise people’s lives, and, while they share a common origin, they developed differently in various groups according to emerging needs. The study also provides an update to the basic ethnographic data on the Karimojong, Jie, and Dodoth generation-sets. For reasons of stringency, no reference is made here to related social categories like lineage, clan, stock ownership, etc.