Cognitive deficits constitute a core symptom in schizophrenia, are difficult to treat, and have special relevance regarding prognosis and functional outcome. The search for pharmacological strategies for improving cognition in schizophrenic patients has been hindered by the lack of a consensus regarding instruments for cognitive assessment. The 'Measurement and Treatment Research to Improve Cognition in Schizophrenia' (MATRICS) initiative of the U.S. National Institute of Mental Health (NIMH) set the development of a consensus cognitive battery as one of its objectives. In a first phase, the seven cognitive domains which have been shown to be impaired in schizophrenia and that were to be assessed were identified: Speed of processing, Attention/Vigilance, Working memory, Verbal learning, Visual learning, Reasoning and problem solving, and Social cognition. In a second phase, the MATRICS Consensus Cognitive Battery (MCCB) was developed. This is a cognitive assessment battery composed of ten instruments, which assess the seven domains in a little over one hour. The MCCB has been standardized in U.S. population, and the Spanish standardization has been recently published.