Popular media would have families believe that Tourette Syndrome (TS) is an extreme and bizarre condition, defined by swearing and outlandish symptoms; this is not helped by the fact that many front-line health professionals like family doctors are not trained in this disorder. In actual fact, the average case of TS is mild. The diagnosis requires only one phonic tic (involuntary sound) and two motor tics (involuntary movements) to be present before age 18 (not necessarily at the same time even) and for at least one year without being caused by a substance or medication. Not only isn’t a swearing tic (called "coprolalia") necessary for diagnosis, but it is an exceedingly rare symptom – only about 7% of individuals with TS have this tic, and it more rare in children and in mild cases.

Children with tics who do not fit the criteria for TS may be diagnosed with a chronic tic disorder, or transient tics, but these diagnoses differ only in matter of degree or severity from TS; the underlying understanding and management of the symptoms does not change.

Tics can be simple movements or sounds (common ones include excessive eye- blinking/widening/winking, head jerks, throat-clearing, shoulder shrugging, sniffing, and facial grimacing) or more complex movements or sounds that might appear more purposeful (examples include repeating your own words or actions, repeating the actions or words of others, "packages" of simple tics that occur together in an "all-or-none" fashion, "hair-out- of-eyes" movements, writing tics, unusual postures, and stepping patterns or hopping).

Symptoms typically wax and wane (i.e. "come and go", or increase and decrease in severity over time and environment), change, and are suppressible – tics can be held in for short periods of time with varying success (depending upon such factors as age, cognitive functioning level, awareness of tic symptoms, and symptom severity). This is because it seems that the truly involuntary aspect of most tics is the URGE to tic (known as a "premonitory urge"), rather than the action itself. While suppression is not a viable management alternative (the control is imperfect, conscious, and requires increasing amounts of effort over time thereby influencing things like attention and frustration tolerance), it IS a unique aspect among movement disorders.

Two factors that are known to exacerbate tic symptoms are increased concentration on symptoms (resulting in a child paradoxically engaging in certain symptoms more after they are told to stop, for instance, which could be misinterpreted as oppositional behaviour) and stress (including excitement over positive events).

About 1% of the population around the world fits criteria for TS. The prevalence is higher in males, and is proportional across the normal curve of intelligence to that of the population as a whole. In other words, while the vast majority of individuals with TS fall within the average range of intelligence, it is expected that approximately 3% will be gifted, and 3% will be developmentally disabled.

Finally, a number of other conditions commonly co-occur with TS, including poor motor skills, Attention-Deficit/Hyperactivity Disorder (ADHD), Obsessive-Compulsive Disorder (OCD), sensory processing dysfunction, and learning disabilities. When an individual must contend with components of many or all of these disorders, Oppositional-Defiant and Intermittent Explosive behaviours can also appear; these symptoms are secondary to (and often indicative of) this struggle and are not in and of themselves diagnostic of TS.