Civil society organizations play several important roles in supporting tax transparency, accountability, and taxpayer engagement. They provide capacity building and advisory services to tax authorities and governments. They also promote tax transparency through initiatives that share tax information with the public and encourage revenue reporting and audits. Additionally, civil society organizations educate taxpayers, raise awareness of the importance of taxation, and advocate for responsive tax policies. However, they face challenges like lack of data and resistance from some governments. Overall, civil society helps strengthen tax administration and holds governments accountable for tax revenue expenditures.