Using Polish panel data from 1998, 2003, and 2008, I examine people’s knowledge of the governing parties of the Sejm in 2003. I focus on ability, opportunity, and motivation to explain political knowledge. I also examine the effects of knowledge on changes in political attitudes and behaviors from 2003 to 2008. Major sources of political knowledge are prior political interest and the change in interest from 1998 to 2003, political experience, and cognitive ability. There also exists a substantial gender gap in knowledge. Finally, political knowledge leads to changes in political interest, alienation, democratic attitudes, and voting behavior.