What factors enable and motivate citizens to form partisan identities? Popular accounts, as well as several major theoretical approaches, attribute a central role for policy and ideological concerns in shaping the partisan orientations of voters. Information about the policy aims of parties should therefore, on average, make it easier for an individual to find a party that best fits her views, especially if she had previously been less familiar with the parties. The evidence for this is mixed, however. Plenty of studies find a robust correlation between policy views and partisanship. Yet there is mounting evidence that citizens look to parties to decide where to stand on policy issues, suggesting that partisan identification precedes policy preferences. We bring new evidence to bear by investigating directly the impact of substantive policy information on the partisan identities of ordinary citizens. To do this, we carry out a pair of original experiments across six countries, five of which are relatively young or unstable party systems. One experiment informs citizens about the policy goals of the major parties; we find little to no evidence that such information affects levels of partisanship. The other experiment tests the impact of inviting citizens to evaluate and compare their own position to the positions of the major parties, a more direct test of the sort of reasoning posited in some theoretical accounts. We find that this reflective task in fact depresses levels of partisanship, perhaps especially among those who knew less about politics and parties from the outset. This suggests that thinking about policy differences and proximities pushes citizens away from partisan attachments they form in the ordinary course of life, perhaps because such thinking generates fresh doubts or focuses attention on facets of partisan choice that matter less in typical processes of preference formation.