Discrete trial training (DTT) is a technique used by practitioners of applied behavior analysis (ABA) that was developed by Ivar Lovaas at the University of California, Los Angeles (UCLA). DTT uses direct instruction and reinforcers to create clear contingencies that shape new skills. Often employed as an early intensive behavioral intervention (EIBI) for up to 30–40 hours per week for children with autism, the technique relies on the use of prompts, modeling, and positive reinforcement strategies to facilitate the child's learning. It previously used aversives to punish unwanted behaviors. DTT has also been referred to as the "Lovaas/UCLA model", "rapid motor imitation antecedent", "listener responding", errorless learning", and "mass trials". Technique Discrete trial training (DTT) is a process whereby an activity is divided into smaller distinct sub-tasks and each of these is repeated continuously until a person is proficient. The trainer rewards successful completion and uses errorless correction procedures if there is unsuccessful completion by the subject to condition them into mastering the process. When proficiency is gained in each sub-task, they are re-combined into the whole activity: in this way proficiency at complex activities can be taught. DTT is carried out in a one-on-one therapist to student ratio at the table. Intervention can start when a child is as young as two years old and can last from two to six years. Progression through goals of the program are determined individually and are not determined by which year the client has been in the program. The first year seeks to reduce self-stimulating ("stimming") behavior, teach listener responding, eye contact, and fine and gross motor imitation, as well as to establish playing with toys in their intended manner, and integrate the family into the treatment protocol. The second year teaches early expressive language and abstract linguistic skills. The third year strives to include the individual's community in the treatment to optimize "mainstreaming" by focusing on peer interaction, basic socializing skills, emotional expression and variation, in addition to observational learning and pre-academic skills, such as reading, writing, and arithmetic. Rarely is the technique implemented for the first time with adults. DTT is typically performed five to seven days a week with each session lasting from five to eight hours, totaling an average of 30–40 hours per week. Sessions are divided into trials with intermittent breaks, and the therapist is positioned directly across the table from the student receiving treatment. Each trial