There are many variables that can have an effect on the use of retention versus aspiration of the phoneme /s/ in the Spanish language, i.e. age, social class, gender, word position, and style of speech. This study deals with the effect of gender of the speaker on the rate of retention and aspiration of the /s/ in the city of Barranquilla, Colombia. As part of the Caribbean coast of Colombia, its linguistic variations are usually more consistent with other Caribbean cities rather than with the interior of the country. Previous studies have found that aspiration is the preferred variable by both genders in these locales. But will Barranquilla follow this trend? Or will the people of Barranquilla follow that of other cities where women prefer the standard or more normative variable, retention, and men prefer the less standard variable, aspiration. This book looks at previous studies focused on gender differences in speech, the phoneme /s/, and the combination of the two. The resultsof this investigation are presented with clear examples and then compared to previous studies. Then, possible explanations for variations and ideas for future studies are discussed.