In recent years, several countries worldwide have been committing to open data principles, and public institutions in these countries have been making their datasets available, free of charge, for re-use. There are currently numbers of issues preventing a full exploitation of open government data (OGD), and this thesis intends to advance OGD research in three areas: user needs (what are needs and wishes of OGD users?), user information (how to effectively inform OGD users?) and user empowerment (how to enable OGD users to effectively re-use OGD?). A set of contributions in this work offers insights into the needs of OGD users in Columbia and Spain (user needs). In addition, the thesis offers an empirical comparison of geovisualizations and data tables for information provision in the OGD landscape (user information). Finally, this thesis proposes an approach that enables people without programming and Cartography expertise to create thematic web maps (user empowerment).