High-performing adults with compensated dyslexia pose particular challenges to dyslexia diagnostics. We compared the performance of 20 multilingual Finnish university students with suspected dyslexia with 20 age-matched and education-matched controls on an extensive test battery. The battery tapped various aspects of reading, writing, word retrieval, phonological processing and other cognitive functions relevant for dyslexia. Reading and writing were examined in the two domestic languages, Swedish and Finnish. The most prominent group differences in reading and writing emerged on accuracy measures in both languages (reading text aloud, proofreading, writing to dictation, free writing). The dyslexia group also performed less well on speeded segmentation of written input, complex speeded naming and complex phoneme manipulation. The pattern of results fits the phonological deficit hypothesis of dyslexia and indicates the presence of pervasive underlying deficits in compensated dyslexia. Copyright (C) 2010 John Wiley & Sons, Ltd.