In recent times, decision outsourcing IT activities in the public sector is fast evolving in the world at large. This fact has been considered as a high level of strategic measure used in different industries particularly in the public sector where internal IT expertise is found wanting in the area of implementing IT activities to improve the performance growth of the public sector. Although outsourcing IT activities are beneficial to IT Practitioners, Decision-makers, and heads of departments, but the fact remains that choosing the right IT Provider is still a challenge that is inevitable to be avoided as they continue to make the mistake of choosing the wrong IT Provider during outsourcing provider selection. This study considered mainly the approach undertaken towards achieving the key objective of this paper which is the development of the proposed model that can support IT practitioners in outsourcing selection practices. However, this paper considered an appropriate technique that can be implemented in an uncertain and complex situation. Having reviewed thoroughly five existing techniques used in the prior researchers' work, in-depth understanding on this justified that, fuzzy logic and its particular tools used Fuzzy Inference Systems (FIS) was found to be considered efficient and suitable for outsourcing selection practices in an uncertain and complex situation. Also, a pilot study and empirical study were conducted to ascertain the validity of the instruments (questionnaire data). The pilot study consists of 33 respondents while the empirical study consists of 133 respondents. Finally, the reliability test was carried out to determine the validity and reliability of the six influential factors selected, thereafter the proposed model was developed. The application of the developed Decision Outsourcing Selection Model (DOSM) will aid the IT Practitioners in their decision outsourcing Selection practices.