Electronic Participation (e-Participation) initiatives, seen as the use of information and communication technology (ICT) for facilitating citizen participation in the policy decision making process, have often had a limited success of citizens' engagement. Despite utilizing social media as a potential solution to remedy this limitation, many of such initiatives particularly those sponsored by governments, continue to suffer of low citizen involvement. This fact raises crucial questions about citizens' incentives, attitude and adoption towards this interaction. While e-Participation initiatives seek to empower citizens with ICT so as to be able to involve and impact decision making processes. Typically, examining and predicting citizens' engagement cannot exclude the possibility role of various human behavior factors besides technology one. Significantly, information systems (IS) discipline consider the intersection of artifacts, humans, and tasks when investigate a phenomenon and reveals several theoretical models primarily developed from in psychology and sociology theories. In thus, the current in progress research ultimate aim to derive and validate an integrative citizen adoption model. The model will be based on distilled the main critical social, behavior and technological factors related to the explanation and prediction of citizen' adoption to involve in government-led e-Participation initiatives through social media.