This paper is presenting a case study of Scandinavian Airlines Systems (SAS) showing how improvements of service quality aspects with Avatars can be managed with a Co-Design research approach. The Co-Design practices are carried out in different fields of studies. Some of the key advocates of Co-Design originate from business. In this study the four steps of Co-design approach is applied. From the first step of Co-design, through interviews, log analysis and a channel survey, findings show that the failed dialogues with Avatar Eva are mainly concerned with five factors: interactivity; dialogue capability; consistency; knowledge; and synonyms. In the second step, carrying out customer workshops, we suggested ten ideal scenarios for Avatar Eva to perform better. In the third step, SAS decision makers decided to implement the first three scenarios: Eva's synonyms; knowledge and Eva's consistency. In the fourth step, another channel survey was carried out as well as a new log analysis to know the impact of the redevelopment above three scenarios. An important result of the study was that the company adopted a continuous use of Co-Design as an approach of continuous improvement of the service quality performed by the Avatar Eva. It also opens a new set of questions framing the relation and transformation between Co-Design as a research approach for knowledge creation and Co-Design as a method for innovation and service quality improvements. The study presents an Extended Co-design Model, which illustrates how the Co-Design inspires staff to use it for other functions within and without the SAS.