This study illustrates that role of Lexical Selection (Mascaró 2007) in Optimality Theory in accounting for the Welsh definite article\u27s allomorphy. This is in response to the claims made by Hannahs & Tallerman (2006) that OT is unable to account for the behavior and distribution of the definite article. This study addresses three of the points that Hannahs & Tallerman raised which I am calling the grammar problem, the homophony problem, and the allomorph interaction. I show that Lexical Selection is uniquely adapted to account for each of the points concerning the definite article allomorphy. Additionally, this study proposes that Lexical Selection needs to be amended with multiple Priority constraints that are morpheme specific...