 Carroll received a grant for foreign language learning aptitude research through the Carnegie Corporation and worked with Stanley Sapon and the US Army-Air Force to develop the MLAT.The MLAT was first published in 1959 by The Psychological Corporation and was still sometimes used as of 2004.In his paper "Fundamental considerations in testing for English language proficiency of foreign students", published in 1961, Carroll challenged the language testing field's reliance on discrete-point testing.