By using latent profile analysis eight stable and interpretable subgroups of readers were identified. The basis for subgrouping was different performance measures with four aspects of reading in focus: reading of continuous texts, reading of document texts, word reading and reading speed. Participants were 9-year-old Swedish students included in the International Association for the Evaluation of Educational Achievement (IEA) Reading Literacy Study in 1991 (n = 4,184) and in 2001 (n = 5,099). The eight subgroups were compared on different background variables, such as gender, language at home, and cultural and socioeconomic factors. It was concluded that latent profile analysis proved to be a feasible methodology. The even performance profiles of good and average readers imply that reading is a skill with a high degree of transfer and generality. Several subgroups of poor readers with more heterogeneous performance patterns could be identified. The three most stable subgroups proved to be comprised of high performers, poor comprehenders and dyslexic students.