These are students who are exceptionally able but also present with an additional disability such as an autistic spectrum disorder (ASD) or an emotional disturbance, a hearing, speech or visual impairment, physical disability or a specific learning disability. These students defy the notion of 'global giftedness', a phrase that denotes ability or talent in all academic areas. Students who are both exceptionally able and have a learning disability exhibit remarkable talents and strengths in one area, while also exhibiting the characteristics associated with the additional disability. These students are often under-identified in the exceptionally able population. Some characteristics to look for when attempting to identify these students are as follows: evidence of an outstanding talent or ability; a discrepancy between expected and actual achievement; and evidence of a processing deficit (e.g. students with visual or auditory processing deficits may underachieve in basic academic areas because of underlying difficulties that the brain has in processing and making sense of some types of visual and/or auditory information that it receives).

There are at least three subgroups of students whose dual exceptionality may remain unrecognised in school:

• students who have been identified as exceptionally able, yet exhibit difficulties in school. These students are often considered underachievers, and their underachievement may be caused by poor self-image, lack of motivation, or even laziness. As school becomes more challenging, academic difficulties may increase to the point where the student is falling significantly behind peers.
• students whose learning disabilities are severe enough that they have been identified as having learning disabilities, but whose exceptional abilities have never been recognised or addressed. Difficulties in assessing these students on standardised IQ (Intelligence Quotient) tests often lead to underestimation of these students’ intellectual abilities.
• students whose abilities and disabilities mask each other, so that students are considered to have average abilities. Because these students typically function at normal school level, they are not seen as having problems or special educational needs. Their academic difficulties usually increase to the point where a learning disability may be suspected.