Empirical measures of gender inequality lag behind the more sophisticated conceptual discussion of gender in the capabilities approach. This is due to a range of conceptual and empirical challenges associated with measuring gender inequality in capabilities. They relate to the distinction between well-being and agency, possible gender differences in needs and preferences, as well as household-based instead of individual-based assessments of well-being. As a result, it is very difficult to empirically assess gender inequalities in capabilities with a sufficient amount of accuracy and reliability. In contrast, more progress can be made in documenting gender gaps in functionings. This can be done by using all available individual-level information in standard household surveys, extending these surveys to include more individual-level indicators, and by relying on custom-made data for more detailed assessments. At the same time, measured gender gaps in functionings are not easily interpreted. While in some cases, it is relatively easy to conclude that such gaps imply unequal treatment and discrimination, not all observed gaps can be interpreted in this way. We therefore need to be more circumspect when interpreting gender gaps in functionings, and particularly try to understand much better why these gender gaps exist and, in many cases, persist.