The evaluation of bilingual education in the Basque Country has gone through different stages during the last 25 years. From 1983 onwards, language models of schooling A, B and D were developed, according to parental choice. Model A is not considered a bilingual education model, since L2 is taught as a subject only, while models B and D are immersion programmes. The first doubt that arose in those years was whether the learning of L2 would affect the competence level of pupils in L1, and how the different language models of schooling would function. This was the main reason for the EIFE 1, 2 and 3 studies and the HINE study. These evaluations compared models A, B and D on scores obtained in the two official languages. Around 1995 a new phase started in Spain when the first evaluations of academic achievement in Primary Education were set up. Many people were convinced then that bilingualism had a price, and that the academic achievement of bilingual pupils would be lower than the academic achievement of monolingual pupils. This preconception vanished when the results of the 1995 evaluation mentioned above were known: the Basque Country and Navarre obtained the best scores in all Spain. Later in 2000, the PISA International Evaluation of the OECD raised the issue of the language used to administer the test: in which language do pupils score better? Finally, in 2004, the Basque education system was evaluated using the Common European Framework of Reference so as to find out the level of competence pupils reach at the end of compulsory education.