Stuttering is a disruption in the forward flow speech characterized by sound and syllable repetitions (e.g. g-g-going) and sound prolongations (e.g. gooooing or ....going).

While many children exhibit breakdowns in fluency, these breakdowns usually occur as repetitions of whole words (e.g. mommy, mommy, can can can I go outside) or phrases (I want, I want, I want to go.) In contrast, many children who stutter begin producing stuttering type disfluencies right from the onset of their problem. When a child is producing 3 or more of these stuttering type disfluencies in a 100-syllable conversational sample, a parent should consult with a speech-language pathologist who specializes in the area of stuttering.

Other struggle behaviors are also common in individuals who stutter. There may be excessive movement of the muscles of the face and neck, and eye contact with the listener is frequently broken. In addition, secondary behaviors may co-occur. These behaviors are particular to the individual and are used in order to help release the blocked sound or word. For some individuals, there may be a habitual turn of the head, for others, a snap of the fingers or protrusion of the tongue. Secondary behaviors develop as the individual tries to cope with his stuttering.