Type-Logical Lexical Functional Grammar is a new, radically lexicalist, and formally parsimonious theory, in essence a re-incarnation of Lexical Functional Grammar (Kaplan and Bresnan 1982) in a type-logical formal framework very similar in formal nature to that of Type-Logical Categorial Grammar (Morrill1994, Moorgat 1997). It puts emphasis on having a simple logical foundation as its formal basis and no empirically unmotivated primitives, representations, and mappings between them. It differs to TLCG in basing syntactic analyses on functional rather than constituent structure, to both LFG and TLCG in that it rejects syntactic categories as primitives, and to LFG in that it rejects c-structure as a linguistically significant representation and in being radically lexicalist. The present paper presents TL-LFG, the sequence of developments that lead to it, and its key differences to LFG.