Motivated by polar extremes of monopartisanship and nonpartisanship inexisting literature on parties in legislatures, we introduce and analyze amore moderate theory of competitive partisan lawmaking. Thedistinguishing feature of competitive partisanship is that the minorityparty, although disadvantaged, has some guaranteed opportunities toinfluence lawmaking. Our analytic framework focuses on two dimensions ofparties in legislatures: agenda-based competition,operationalized as a minority party right to make an amendment to themajority party’s proposal, and resource-based competition,characterized as the ability of both party leaders to use transferableresources when building winning or blocking coalitions. Building on thecanonical model, we find that giving voice to the minority party in eitherone of these ways alone results in outcomes that, on the whole, are lesslopsided and more moderate than those predicted by the existing monopartisanand nonpartisan theories.