This study intends to characterize the practices of public relations agencies and companies in the Sultanate of Oman of their work in light of the Excellence Theory of public relations. It focuses on two aspects: the internal organization of the agencies and companies and the services provided for clients. The study used SABCO guide book (media te: 2015/2016) to extract the sample of the study, which covers the public relations agencies and companies in the Muscat Governorate only, administering one questionnaire per each agency or company, The study depends on survey methodology, via using an Arabic and English questionnaire as a tool for data collection. The questionnaire was distributed among executives or their representatives in the agencies and companies subject to study. The results show that the public relations agencies and companies in the Sultanate of Oman abide by the actual reality of the excellent practices of the public relations profession to some extent; as they follow the characteristics of the Excellence Theory of Public Relations in some aspects, and fail to implement them in others. For instance Public relations agencies and companies in the Sultanate of Oman empower the public relations function; in terms of managing communication programs strategically, and in terms of involving public relations practitioners in the Strategic Management, but they don't empower the public relations function in terms of involving the public relations practitioners in the formation of the board of directors of the agencies and companies subject to this study. The study also complies with the characteristics of the Excellence Theory of Public Relation in terms of providing diversity of administrative and technical roles of the public relations function, and in terms of enabling men and women to practice the two types of roles. On the other hand the results don't comply with the characteristics of the theory in terms of providing equal opportunities for men and women to practice the administrative role and in terms of giving women the right to be represented equally with men, as women are better than men in communication practices according to the Theory speculation. The results of the study match the characteristics of the theory on the aspect of organizational communication function and its relationship to the other management functions in terms of considering public relations as an integrated communication function, and don't match the characteristics of the theory in terms of considering public relations a non-separate department or function from the other departments or functions. The study concludes that the two way symmetrical model is the most used model by the public relations agencies and companies in the Sultanate of Oman, as it is considered the best model in public relations practice according to the characteristics of the Excellence Theory of Public Relations.