This unit is geared towards investigators wishing to study the effects of externally and internally applied agents on the behavior of ligand-gated ion channels (LGICs, specifically the GABAA receptor). The reader is taken through a number of electrophysiological techniques applied to whole cell and excised patch recordings of recombinant and native GABAA receptor subtypes used in the generation and analysis of a variety of pharmacological parameters. These data interpretations form the basis for the analysis of potentially novel pharmacological agents active at the GABAA receptor target, but could equally be applied to other LGICs. The analysis is extended to incorporate post-synaptic inhibitory events in hippocampal neurons. Complementary descriptions of how tissues for such studies are prepared from recombinant and native receptor preparations are included. Attention is given to the physiological phenomena most relevant to everyday scientific literature.