Many claims have been made about the positive impact that transitional justice can have on societies recovering from violent conflict. Sceptics argue, however, that many transitional justice measures can undermine negotiated settlements and exacerbate divisions. There is growing recognition of the need to engage in more systematic research on the effects and impact of transitional justice; however such empirical research is still in the early stages. Nonetheless, the literature identifies some factors which contribute to the effectiveness of transitional justice (whether supported through international assistance or domestic resources). These include: legitimacy and local ownership; government commitment; involvement of civil society; outreach; capacity building; appropriate timing; the use of a combination of mechanisms; and empirical research.