This study focuses on issues in interorganizational cooperation to explain network relationships and their effect on company performance in South Sudan. According to the South Sudan National Bureau of Statistics, by June 2010, registered companies in the country were 7,333. Prior to this study, there appeared to be no study done concerning the interorganizational networks in South Sudan. The study builds on the recent studies of relations, selection and motives on organizational performance. The researcher adapted and modified the framework of previous researchers. This study excludes the mediating variable of interorganizational commitment to test directly the constructs of loose and soft, and hard explicit motives; trust and reciprocity, and expected goal congruence and network awareness. The sample consisted of randomly drawn 184 companies in South Sudan. The data was collected in December 2012 using questionnaires and analyzed using SPSS to distil descriptive data and conduct factor analysis. The research objectives are to test the effects on performance of: initial motives; criteria of selecting a partner; influence of trust, and the influence of reciprocity. The research question is: What effect does social capital capitalized from partner goals; selection, and motive have on organizational performance? To achieve the specific objectives of the research, six (6) hypotheses were developed. The study findings are that loose and soft-, and hard partner motives, partner selection and reciprocity had an effect on organizational performance while trust did not. The implications of this study are that companies that are involved in interorganizational networking and seeking to perform need to invest resources of time and money in clarifying their motives; learn from partners; select partners; match mutual goals; keep a database of potential partners; practice reciprocation, and build relationships that rely more on control and legally enforceable contracts. This study has contributed to the response to the main problem of lack of researched studies in interorganizational cooperation with in South Sudan. The study has blazed the trail for further study on the topic of interorganizational cooperation in the country. The specific contribution of the study is that it has confirmed that five of the conceptualized constructs affect organizational performance and trust does not affect performance in the Republic of South Sudan. The study has contributed to obtaining evidence of how these outcomes occur within this setting.