Introduction The study of personality is a broad study that goes back to the Greek philosophers Hippocrates and Galen. Personality psychology involves a person’s motivational and attitudinal attributes that are pivotal in the selection, interpretation and processing of information from the internal and external environment. Human actions and behavior can well be understood if we are aware of the fact that the prism of the mind orders the experience of the situation. People do not only respond to the objective characteristics of a situation but they pay more emphasis on the meaning that situation presents to them. It is from this background that this paper seeks to inquire into the role of personality in shaping interpersonal relationships at the workplace. It adopts a humanistic approach in describing the role of personality in shaping the behavior of people. The first section presents a situational synthesis of the pivotal role of personality in social skills, training and its implication in the working environment. The second section explains on the interpersonal relation associated with the workplace. The practical application of personality in this situation observes that behavior is much hinged to the situation a person is exposed to; hence the last section gives recommendations on how the working situation can be improved. Humanistic/ Existentialistic approach in understanding personality: A practical situational analysis Salesmen’s performance at work is pegged on motivation, deviation, job satisfaction and teamwork at the workplace. They are motivated either to improve on their status or on the achievement of tasks assigned. Extraversion is a necessary aspect of a salesman. Openness to experience as demonstrated by the extrovert salesman positively correlates to job satisfaction while the introvert salesman is reserved. The social environment of the workplace determines the level of arousal. Extroverts experience their optimal points of arousal in the work place as opposed to introverts who are highly aroused outside the workplace. The personality of the Salesmen is crucial in the deviation at the workplace. This occurs when an individual voluntarily resolves to actions that threatens both the individual and the company. Interpersonal deviance such as hostility and rudeness towards other people and organizational deviances such as stealing and withholding efforts demonstrates the role of personality in the workplace. Salesmen who have a positive attitude towards the workplace are less likely to pursue deviant behavior than those with a negative perception towards the job and the workplace. Introverted conscientious salesmen are likely to be present at work. Extraverted salesmen are more satisfied in the workplace while their introverted counterparts are kess satisfied in the workplace. Extroverts have friends that motivate them to go to work as opposed to introverts who skip work to avoid extra stimulation. The perceived limitations of psycho dynamics theories in their failure to convincingly address and explain issues such as the meaning of behavior gave birth to the humanistic approach. This approach is distinct from other approaches in the way it understands the human to be challenged by temporary existence. Humanist