This thesis focuses on the transferability of grammatical competence to grammatically correct performance in the future tense in 10th grade German students who were learning English as a Second Language. The goal was to suggest an empirical contribution to the issue of whether implicit or explicit knowledge of grammatical rules or grammatical competence has any direct impact on its correct application in grammatical performance. Student communicative effectiveness was assessed using a passive grammar test, an implicit/explicit test, and a performance letter writing test with focus on content. Results indicate that 93.3% of students gave evidence of a transfer of competence to performance when using the English future tense, suggesting that grammar practice should be kept in a communicatively-oriented framework to make transfer easier. Test materials and quantitative data results are appended. (Contains an extensive list of references.) (NAV)