This monograph examines three approaches to intelligence that include cognitive processing components and relates each to assessment and interventions with students having reading disabilities. The first, Sternberg's Triarchic theory of intelligence (1985), includes three subtheories, contextual, experiential, and componential. The second, the Campione-Brown theory of intelligence (1978), utilizes an information processing model that proposes two hierarchical levels, the architectural system and the executive system. The third is the Planning, Attention, Simultaneous, Successive (PASS) theory of intelligence (1994). Empirical research on reading disabilities from the perspective of each theory is briefly reviewed, which shows the Triarchic theory to be a multifaceted approach to reading difficulties, the Campione-Brown theory's components (short-term and working memory, knowledge base, and control processes) to be especially relevant, and the PASS theory to be relevant at both the decoding and reading comprehension stages of reading. Evaluation of the theories' implications for assessment and intervention identifies promising assessment instruments and instructional systems based on each theory. (Contains approximately 90 references.) (DB)