In this work, Udel® polysulfone was functionalized with quaternary ammonium and phosphonium based cations for thin-film anion exchange membranes (AEMs). At this time, discussion is limited to the chemical, mechanical, and thermal attributes of quaternary ammonium polysulfone (QAPSF). Key results indicate that the thermal properties of QAPSF are well suited for low temperature fuel cells, but improvement to QAPSF conductivity and mechanical properties is needed for durable and high performing alkaline fuel cells. It was observed that water uptake of nearly 15% of the normalized membrane weight is needed to facilitate ion conductivity in the QAPSF membrane. Finally, fuel cell performance is demonstrated with a QAPSF membrane electrode assembly.