A revisionist literature in political science and sociology argues that NGOs are collective organizations that seek to balance both strategic and principled concerns in their choice of activities.  A key strategic choice facing many development NGOs is the decision about whether to engage in policy advocacy and lobbying. Rights-based approaches to development increasingly stress the need to address underlying policies and structural conditions in the fight against poverty.  As a result, many international NGOs are transitioning to a rights-based approach, typically implying a stronger focus on advocacy. This may place increasing pressure on local NGOs to engage in advocacy efforts.  But local NGOs in many developing countries may also face pressure from governments to refrain from particular kinds of programming, particularly advocacy or lobbying activities considered ‘political.’ How do NGOs balance these concerns and what is the relationship between funding mix, NGO-government relationships, and advocacy activities? In this paper we investigate the factors associated with advocacy efforts on the part of NGOs in Cambodia with a particular focus on how existing relationships with the government affect advocacy activities. Advocacy NGOs are often highly visible in democratic setting with open media and free speech and association, but advocacy takes place in less open societies as well, although the form it takes and the channels of influence may differ.   We use an original dataset based on interviews with 135 NGO managers in Cambodia to investigate NGO engagement in advocacy. Many NGOs in Cambodia are engaged in a blend of service delivery and advocacy, so that their orientation may differ from the kinds of organizations typically studied in the advocacy literature. In the Cambodian setting, we argue, even relatively minor attempts to engage and influence the government beyond service-delivery could be considered a form of advocacy.  We consider four sets of factors that might be associated with such activity.  First, we examine whether collaboration or coordination with government is associated with efforts at advocacy and influence.  In an authoritarian setting like Cambodia, outright opposition to the government is likely to result in reprisals or closure. Constructive engagement may be the most productive way to create space to engage in advocacy efforts. Following the sociological literature we also examine the impact of organizational rationalization and professionalization on advocacy efforts and whether embeddedness in local society and networks enables or constraints efforts at influence.   Funding sources may also inhibit or support efforts at advocacy and we look at whether the types of funding sources, including government funding, affect advocacy efforts. We find that NGOs with local (rather than expatriate) leadership that were already engaged in coordinated activity with the government were more likely to engage in advocacy.  In a relatively authoritarian setting like Cambodia, such relationships may be necessary for constructive engagement. Professionalism and rationalization were not associated with advocacy, while NGOs with earned income were less likely to engage in advocacy. The results suggest that more market-oriented NGOs may be less likely to engage in advocacy, even controlling for other sources of income.