Gabriel Sipos is an executive director of Transparency International Slovakia, the most influential anti-corruption NGO in the country. His organization helped introduce radical transparency reforms in Slovakia, such as mandatory publication of government contracts as well as judicial contracts online. TI Slovakia regularly measures transparency in rankings of Slovak state-owned companies and municipalities. In the last few years it helped create some of the most interesting open data applications, such as court and judge profiles (http://otvorenesudy.sk/), public contracts (http://otvorenezmluvy.sk/), and government procurement deals (http://tender.sme.sk/en/). Before joining TI Slovakia Mr. Sipos wrote Slovak Press Watch (http://spw.blog.sme.sk/), a highly influential local blog. For the last few years he has been among the 5 most cited experts on government affairs.