This document provides an introduction to the Gap Model of Service Quality. It discusses the five gaps identified in the model: 1) the gap between customer expectations and the company's understanding of those expectations, 2) the gap between management's perception of customer expectations and service quality specifications, 3) the gap between service quality specifications and service delivery, 4) the gap between service delivery and external communications about the service, and 5) the overall gap between expected and perceived service quality. The document focuses on applying this model to analyze service quality in retail companies.