Indicators have become an important tool for policy actors at the bilateral and multilateral level over the past twenty years; however, they have mainly been developed in relation to development and public health goals. This note identifies the practical and methodological challenges in developing global (i.e. cross-national) indicators for transitional justice, through reflection on a practical engagement with UN Women, for which the author developed two indicators on women’s participation in truth commissions and in reparations programs. Specific challenges to developing the indicators included: the lack of administrative data on transitional justice; difficulty in establishing agreed definitions on “what” is being measured, which is linked to the lack of common agreement on the objectives of transitional justice initiatives; lack of standardization of data collection practices across countries; lack of engagement between transitional justice institutions’ staff and statisticians; and the general challenges in measuring progress against human rights objectives. I introduce a “basket” approach as an imperfect solution to this data reality. The note concludes by identifying specific changes that would ease the process of developing meaningful cross-national indicators on transitional justice.