An active, stable, and selective catalyst for ethylene oligomerization is developed. Fundamental modeling is carried out using Single-Event MicroKinetics (SEMK). Model parameters are determined which can be classified as kinetic and catalyst descriptors. The first type of parameters is specific to the reaction family considered and independent from the catalyst, while the latter accounts for the effect of catalyst properties on the kinetics. When brought into contact with an acid catalyst, ethylene is relatively stable at mild conditions because it can only form primary carbenium ions. A metal ion function is introduced to activate ethylene and dimerize it to butylene. Consecutive ethylene insertions are possible on metal ion sites and also on the acid sites because of the involvement of more stable secondary carbenium ions. This is an abstract of a paper presented at the 2011 AIChE Annual Meeting (Minneapolis, MN 10/16-21/2011).