Counts of register features have produced useful data on varieties of written English and on differences between writers of differing writing and language proficiency. This article reports an attempt to extend this procedure to an evaluation of the same foreign-language writers at two different stages. It shows that the procedure can differentiate the products of developing writers at two relatively close points in time, and that a more detailed examination of significant changes can be revealing about patterns of learning. The major changes were from features of spoken English to those more typical of formal writing, both in surface detail and in more fundamental characteristics. There was less change in complexity of construction or variety of vocabulary, Improved correctness in the structures used was balanced by errors in new structures being attempted. The subjects had been discriminating in their acceptance of academic style and actively sensitive to genre and other requirements.