AbstractThe present research was directed toward the understanding of diagnostic problem‐solving behavior of expert practitioners in the field of education. By means of educational and psychological tests, ten practicing reading specialists thought aloud about the same case. After the protocols had been transcribed, scoring was on which information cues were used and which diagnoses and remedial prescriptions were formulated. Despite choosing from common information sources, there are substantial differences among the experts in diagnoses and in recommendations. Neither are there any indications for a consistent relation between diagnoses and remediations. Even experts with a similar training come to little agreement. The results are replicated in a second study with a different case diagnosed by ten different experts. The implications of the results are discusse