When firms are doing business it is important to meet the customer’s expectations. It is often in the first impression (the first time the parties meet in a sales encounter) that the seller fails to do this, sometimes resulting in the prospective customer dropping the whole thought of a business deal and no further relationship is established. The first impression results from the first image and understanding a seller creates in a potential customer: here the latter gets a brief insight into the former’s organization, credibility and overall quality. Each encounter or meeting is an opportunity to achieve trust and build a relationship, but also contains the risk of reducing credibility and losing all chances of a relationship. The purpose of this thesis is to describe and analyse the importance of the first impression when creating and building a business to business relationship and to describe the factors which influence this process. The theoretical framework is based on theories regarding the concept of first impression and the implications of two-way communication during the first encounter. These include the seller’s preparation and categorisation of the customer before each encounter. Other variations of communication concerns verbal and non-verbal communication, generalizations, cultural differences and circumstances where a failure can turn into an advantage. The present qualitative case study is based on interviews with five highly competent respondents with long experience of business relationships. They were chosen after discussions with Walter Carvajal, owner and MD of City Guest Service. The results showed that the first impression was very important in creating a business relationship. Some variables, e.g. gender, had less significance. Generally, the first impression included the small things a person perceived and interpreted during the first encounter. Combined, they determined whether a person chose to do business with the counterpart in question. All aspects of verbal and non-verbal commu-nication formed a basis for judging the other person. Cultural differences increased the acceptance level, reducing the risk of failure, when the parties were from differ-ent cultures.