Knowledge transfer in projects are more complex and challenging than such transfers in normal operations due to the temporary nature of project teams in which team members often do not see the capturing and transferring of knowledge across projects as important for long term benefits to the organization. Understanding how and why different communication media, computer-mediated or otherwise, are used in organisations becomes essential to prescribe and to predict sound rationale organisational investments in different media choices. Although a lot of research has been done on factors that influence media selection as a knowledge transfer tool, organisations are becoming more dependent on using the electronic media for communication and further advancement in the electronic media necessitate continued research. This study investigates the key factors that influence the selection of electronic media in projects communication focussing on the engineering sector as well as identifying factors which are more dominant that others. The communication factors which were identified during the study were grouped into four groups: system characteristic factors, task factors, organisational factors and people factors. The study investigated the influence of the communication factors on the following forms of electronic media: e-mail, internet, intranet, extranet, electronic bulletin boards, television networks, audio recordings, video conferences, tele conferences, instant messaging, telephonic systems and multimedia presentations. Results showed that the top ten key factors which influence selection of electronic media consisted of; six system factors, three task factors, one organisational factor and one people factor. Systems factors were more critical than the other factors in influencing the choice of electronic media.