Depending on whether and how argumental Free Relatives (FRs) resolve instances of case conflict between the requirements of the External (i.e., the matrix) and the Internal (i.e., the relative) Predicate, they can be classified into three main categories: (i) Strictly Matching FRs (e.g., Polish), where the FR pronoun has to comply in morphological case with both predicates (Citko 2000), (ii) I(nternal)-Matching FRs (e.g. German), where the FR pronoun has to comply in morphological case with the Internal Predicate, but not necessarily with the External one (Grosu 1994), and (iii) E(xternal)-Matching FR (e.g., Greek), where the FR pronoun has to comply in morphological case with the External Predicate, but not necessarily with the Internal one ((Stavrou & Philippaki 1987; Horrocks & Stavrou 1987; Chila-Markopoulou 1991; Philippaki & Spyropoulos 1997; Alexiadou & Varlokosta 2007; Vogel 2001; Agouraki 2005; Daskalaki 2008; Spyropoulos 2007). In this paper, I use the Greek pattern as my starting point, and I develop a formal account of the observed cross-linguistic variation, which builds on the KP hypothesis (Lamontagne & Travis 1987).