text: optimum mental ability? what training or licence does a person need to make this kind of judgement? is there a standard scale? what kind of tests & what is the tester looking for? is this labeling, taging, or limiting people? in my country (and in most others, i believe), a person needs to be a registered psychologist, psychiatrist or other mental health/intelligence professional. this will generally involve a bare minimum of 6 years of full-time training. there are a number of intelligence tests out there, however, none of them are really that good.  most intelligence tests are pen-and-paper tests. the weschler intelligence scale is probably the most widely used, or the stanford-binet. they are both pen and paper and consist of a number of exercises. you do the test and then it is marked and your scores are compared to standardized test norms. then an overall iq score is given - but good testers will give you a range that they are 95% certain that your 'real' intelligence would fit in.  most intelligence tests out there are really poor in theory and only measure a few different types of intelligence that should be measured. for example, the wisc-iv for children only measures 4-5 of the 10 types of intelligence that have been proposed by what is currently seen as the best theory of intelligence.  similar things apply to adult intelligence testing.  any intelligence test can only be a rough guide and while there are a number of standardized scales, none of them really do the job well. if you want to get given a test, ask your assessor if they use a cross-battery approach to determine your intelligence. if they do, it means that they will assess more different aspects of your intelligence than if they simply give a single test.   the tester should look at how you perform in a number of different areas. some of these are things like reading and writing or general knowledge (crystallized intelligence, really based in culture and education), while others are more things such as reaction time and processing speed.   i think that it is labelling. in some ways, it can be very beneficial to have a label - for example, a child who has severe developmental delays. without having that label, the child is not likely to be able to get the special help that she or he may need to suceed at life and instead be pushed through a standardized system that he/she just can't cope with. on the other side of the coin is the gifted child who is bored out of their minds at school because they already kinow everything they're being taught. if they want to get into a gifted program, they might need that label!  of course, it could also be limiting - someone who scored as below-average when younger might have simply been in a different developmental stage and really be set to grow up with normal levels of intelligence but will instead always think that they're more 'stupid' than others and thus never really strive.  i hope that helps to answer your question.