The learning of mathematics was addressed in this study, with attention in this first volume focused on defining specific learning styles in mathematics, classifying individuals according to learning styles, relating achievement to learning styles, associating learning styles with localized hemispheric functioning of the brain, correlating learning styles in mathematics with general learning styles, and tailoring teaching strategies to learning styles. The Mathematics Diagnostic/Prescriptive Inventory (MDPI), an individualized instrument assessing mathematical achievement, ability, and learning style, was administered to over 1,200 children, aged 5-18. Results of the testing led to the definition of two distinct mathematical learning styles. Comparing the findings of the MDPI with an exhaustive battery of neurological and neuropsychological tests administered to the same children established, clinically, associations between the child's mathematics learning style and hemispheric preference. A statistical study involving a wide variety of variables in mathematics, neurology, and neuropsychology coded for 220 subjects was also conducted. Results confirm that mathematics learning styles more strongly reflect qualitative aspects of performance than straight success or non-success. Conclusions from discriminant analyses conform closely to the assumption of two distinct learning styles. Examples of prescriptive teaching are included, as well as the MDPI and a sample case study. (MNS)