This chapter aims to explore the performance and emission characteristics of butanol isomers in order to suggest technical improvisations for their adoption as a commercial fuel in spark ignition engines. The limited availability of research works using butanol isomer blends motivates the current work involving an extensive investigation of the alternative fuels as a comparative study. Through extensive evaluation of the prevailing research works, it is found that by substituting pure gasoline fuel with butanol-gasoline blends, an increase in the carbon monoxide and hydrocarbon emissions due to the lower calorific value and higher latent heat of vaporization of butanol fuel can be obtained. However, oxides of nitrogen emissions are found to decrease with reference to that of pure gasoline fuel. The current study is extended to validate the results obtained from a review study by conducting an experimental investigation on an SI engine fueled with n-butanol-gasoline blend and isobutanol-gasoline blend. The concentrations of butanol isomers in the blends are varied from 10% to 30%, and the obtained performance and emission characteristics are compared to that of pure gasoline fuel. It is observed that the experimentally obtained characteristics are in accordance with the results obtained through comparative evaluation. © 2019 Elsevier Ltd. All rights reserved.