In this dissertation the author analyzes the grammaticalization process that has taken place in the development of diminutive suffixes in Modern Spanish. She employs theories of grammaticalization and cognitive linguistics, such as George Lakoff's (1987) theory of metaphor, radial categories, and linguistic categorization to study the different functions of the diminutive: word formation, meaning intensification, meaning attenuation, pejoration, hypocorisms, and diminutives proper, as well new ways to express diminutiveness in Spanish. The author concludes that the multiplicity of functions of the Spanish diminutive reflects a process of grammaticalization, whereby the diminutive has extended its original domain of application from meanings grounded in sensorial experience (smallness in physical size) to more abstract contexts. In so doing, the primitive sense of the diminutive has weakened, resulting in its reinforcement by periphrastic means, using adjectives like 'pequeno' and 'chico'. Through the study of the different functions of the diminutive, the author postulates a network of meanings between central, basic senses of diminutive suffixes and more abstract, metaphorical senses. This is accomplished by means of a proposed radial category for the diminutive involving the core sense 'small' and its metaphorical/metonymic extensions in different semantic directions. The author shows that metaphor is a key element in the conceptual transfer from one semantic domain to another, and that meaning extensions are compatible with crosslinguistic tendencies of semantic change. (Martha Mendoza)