This thesis examines the role of informal employee networks and their potential positive contributions to a successful implementation of disruptive organizational change. It relies on an in-depth analysis of qualitative data, collected in 13 semi-structured interviews. The findings show that in times of organizational change, employees countervail the capacities of their informal networks to optimize organizational effectiveness and efficiency against the effectiveness and efficiency of prevalent formal organizational structures. A central dynamic also detected in the findings is the role of organizational identification as a key driver to engage in informal networks to positively support an organization¿s change process implementation.