Asperger syndrome is a condition marked by impaired social interactions and limited repetitive patterns of behavior. Motor milestones may be delayed and clumsiness is often observed. Asperger syndrome is very similar to or may be the same as high functioning autism (HFA).

Hans Asperger labeled this disorder "Autistic Psychopathy" in 1944, and the cause is still unknown. There is a possible relation to autistic disorder (autism). Some researchers believe that Asperger syndrome is simply a mild form of autism.

The child with Asperger shows below-average nonverbal communication gestures, fails to develop peer relationships, has an inability to express pleasure in other people's happiness, and lacks the ability to reciprocate emotionally in normal social interactions. The condition appears to be more common in boys than in girls. There are likely genetic factors, but some theories suggest a prenatal infection may be to blame.

While people with Asperger syndrome are frequently socially inept, many have above-average intelligence, and they may excel in fields like computer programming and science. There is no delay in cognitive development, in the development of age-appropriate self-help skills, or in curiosity about the environment. Generally, there is no language development delay.

• Abnormal nonverbal communication, such as problems with eye contact, facial expressions, body postures, or gestures
• Failure to develop peer relationships
• Being singled out by other children as "weird" or "strange"
• Lack of spontaneous seeking to share enjoyment, interests or achievements with others (a lack of showing, bringing, or pointing out objects of interest to other people)
• Markedly impaired expression of pleasure in other people's happiness
• Inability to return social or emotional feelings
• Inflexibility about specific routines or rituals
• Repetitive finger flapping, twisting, or whole body movements
• Unusually intense preoccupation with narrow areas of interest, such as obsession with train schedules, phone books, or collections of objects
• Preoccupation with parts of whole objects
• Repetitive behaviors, including repetitive self-injurious behavior

Physical, emotional, and mental evaluations are usually performed to rule out other causes.