The EMILE 4. 1 grammar induction toolbox. The EMILE 4.1 toolbox is intended to help researchers to analyze the grammatical structure of free text. The basic theoretical concepts behind the EMILE algorithm are expressions and contexts. The idea is that expressions of the same syntactic type can be substituted for each other in the same context. By performing a large statistical cluster analysis on the sentences of the text EMILE tries to identify traces of expressions that have this substitutionability relation. If there exists enough statistical evidence for the existence of a grammatical type EMILE creates such a type. Fundamental notions in the EMILE 4.1 algorithm are the so-called characteristic expressions and contexts. An expression of type $T$ is characteristic for $T$ if it only appears in a context of type $T$. The notion of characteristic context and expression boosts the learning capacities of the EMILE 4.1 algorithm. The EMILE algorithm is relatively scalable. It can easily analyze text up to 100,000 sentences on a workstation. The EMILE tool has been used in various domains, amongst others biomedical research, identification of ontologies and semantic learning.