Meta-modeling is raising more and more interest in the field of language engineering. While this approach is now well understood for defining abstract syntaxes, formally defining textual concrete syntaxes with meta-models is still a challenge. Textual concrete syntaxes are traditionally expressed with rules, conforming to EBNF-like grammars, which can be processed by compiler compilers to generate parsers. Unfortunately, these generated parsers produce concrete syntax trees, leaving a gap with the abstract syntax defined by meta-models, and further ad-hoc hand-coding is required. In this paper we propose a new kind of specification for concrete syntaxes, which takes advantage of meta-models to generate fully operational tools (such as parsers or text generators). The principle is to map abstract syntaxes to textual concrete syntaxes via bidirectional mapping-models with support for both model-to-text, and text-to-model transformations.