The gaps model
The gaps model of service quality was developed by Zeithaml, Parasuraman and Berry in 1990. It is a useful framework for understanding service quality in an organization. The gap model consists of 5 gaps (one customer gap and four provider gaps). The most critical service quality gap is the customer gap – the difference between customer expectations and perceptions. Closing the gap between what customers expect and what they perceive is critical to delivering quality service.