The purpose of this study is to examine the mediating effects of social networks dimensions of network degree and network transitivity on the relationships between project communication strategies and perceived project success. This study was motivated by the increased failure of most philanthropic projects in Uganda to meet their explicit objects in terms of time, quality, and budget and enhanced corporate awareness which could be attributed to neglect of ‘soft’ factors. Although numerous classical studies have been undertaken in different domains involving project communication, social networks and perceived project success, no existing empirical study has examined the mediating effect of social networks dimensions on this relationship. A cross sectional data collected by a quantitative survey from all philanthropic projects conducted by commercial banks in Uganda, reveals that network degree is a significant mediator in the relationship between internal project communication and perceived project success while network transitivity is also a significant mediator in the relationship between external project communication and perceived project success Further, the findings confirm a partial mediation between project communication, social network dimensions and perceived project success. This study has both practical and theoretical implications that are well discussed.