This study aims at contributing towards enhancing the existing level of understanding with regard to the determinants of service quality and its effects on the behavior of customers in the Greek banking industry and narrowing the existing literature gap. We expect that the conclusions drawn will be welcome by the management of banking institutions and will be put to good use to progress their competitive market position. Previous research in international markets has shown that the corporate image of banking institutions to a large extend relies upon the excellence of their service delivery and their ability to sustain long-lasting relations with their customers. We hope our findings will become a useful basis for further research in the Greek or other financial services markets. A SERVQUAL type scale is developed especially customized for the Greek banking industry, assess the scale''s reliability and validity and detect its factorial structure. Importance-Performance analysis is employed to provide strategic guidance to Greek banking institutions on deploying their quality efforts and resources towards better matching their customers'' needs and expectations.