The object of this study is to treat pronominalization in Spanish within the framework of generative grammar. (The non-hypenated word "pronoun" refers to the traditional class of words including alguien, algo, el, or ella. The hypenated form, "pro-noun," refers to the underlying lexical entries or feature complexes which share the features [+pro, +noun].) The description here is limited to pronominalizations which can be traced to underlying strings of determiners and pro-nouns. The determiners are the definite and indefinite articles, the demonstratives, and the indefinite determiner, algun- 'some'. This study differs from that of Stockwell, Bowen and Martin principally in that the underlying forms upon which the processes of pronominalization act will be considered feature complexes occurring in the base strings of noun phrases (Chomsky, 1965). It is suggested, for example, that the pronoun, ella 'she', has an underlying pro-noun which combines the features of feminine gender, singular number, and humanness. The processes of pronominalization involve the deletion or retention of these underlying nominal feature complexes. The form, ella 'she', represents the retention of the feature complex indicated above, while the string, el bueno 'the good one', is the result of the deletion of a feature complex combining the specifications masculine gender and singular number. (Author/JD)