Benign childhood epilepsy with centrotemporal spikes (BCECTS) is the most common epileptic syndrome in childhood. The outcome is usually excellent, but there are some atypical forms of BCECTS with less favorable outcomes. The aim of this study was to delineate the frequency of these atypical features among patients with BCECTS.We conducted a retrospective chart study by retrieving the medical records of all consecutive patients with BCECTS who were evaluated in four pediatric neurology outpatient clinics in Israel between the years 1991 and 2008.A total of 196 patients with BCECTS were identified (78 female and 118 male; mean age at time of diagnosis 7.64 years, range 1.5-14). The mean duration of follow-up was 4.43 years (range 2-11). Nine patients (4.6%) developed electrical status epilepticus in slow waves sleep (ESES) during follow-up, four (2%) had Landau-Kleffner syndrome, three (1.5%) had BCECTS with frequent refractory seizures, two (1%) had BCECTS with falls at presentation, one (0.5%) had a "classic" atypical variant, and one (0.5%) had oromotor dysfunction. None had rolandic status epilepticus. Sixty-one patients (31%) had attention deficit hyperactivity disorder (ADHD), 43 (21.9%) had specific cognitive deficits, and 23 (11.7%) had behavioral abnormalities, including aggressiveness, anxiety disorders, depression, and pervasive developmental disorder (PDD).The prevalence of most atypical forms of BCECTS other than ESES is low. There is, however, a high prevalence of ADHD and specific cognitive deficits among patients with BCECTS.